IUMRS-ICAM 2015_Selective Oxidation AHSS and UHSS_OCT 25-29_2015

MATERIALS DESIGN LABORATORY

Surface Selective Oxidation Hot Dip Galvanizing

and Coating-related Properties of

Advanced High Strength and Ultra-high Strength

Automotive Steel Grades

BC DE COOMAN Lawrence CHO Changwook LEE Jonghan OH

Graduate Institute of Ferrous Technology

Pohang University of Science and Technology

Pohang South Korea

Oct 25-29 2015 Jeju Island


Golf 2 (1983-1992) Golf 7 (2014)

Issue 2

Greenhouse gas emissions

Issue 1

Passenger safety

2015 130 g CO2 km rarr 2020 95 g CO2 km

2015 17 kml rarr 2020 25 kmlIssue 3

Fuel efficiency

Introduction


Properties

Processing

Microstructure

PerformanceProperties

Processing

Microstructure

Performance

COST

Regulations

Steel

Unibody

Aluminum

Space frame

CFRC

Skeleton

Introduction

Al-alloy body

Steel frame


Introduction

Prevention of Cosmetic and Perforation Corrosion

CRS

Red rustPaint undercreep

Hot Dip Galvanised

No red rust

laquowhiteraquo rust

Zn-Fe Galvannealed

Low corrosion rate

Excellent paint adhesion

Cosmetic corrosion

Perforation corrosion


Introduction

1 Advanced High Strength Steel

bull First generation DP TRIP CP steel grades

bull Second generation TWIP steel

bull Third generation Medium Mn and PHS UHSS steel grades

2 Coatings issues

bull TRIP steel Si-addition

bull TWIP steel high Mn content

bull Medium Mn steel high Mn content

bull PHS press hardening process parameters

3 Solutions

bull Change the alloy design

bull Change the selective oxides compositionmorphology

bull Surface modificationOxidation-reductionMeO reduction

4 Presentation topics

bull Change the selective oxides by DP control

bull Surface modification by Sn Bi-additions

bull Surface modification by oxidation-reduction

bull Coating modification during press hardening


Snout

An

nealin

g f

urn

ace

Galv

an

neali

ng

fu

rnace

Gas wipers

Zn pot

Introduction


AHSS-driven Continuous Galvanizing Technology

C

20ppm-06 Austenite stabilizer

Solid solution strengthener

Phase fractions

Carbides Carbo-nitride former

Si

005-15 mass-

Al

003-30 mass-

Ferrite stabilizers

Solid solution strengtheners

Cementite suppression

Mn

15-26 mass-

5-7 mass-

15-32 mass-

Austenite stabilizer


Phase fraction control

Hardenability addition

Cr Mo

up to 04 mass- Transformation control

Hardenability additions

V

up to 01 mass- Precipitation strengthener

Carbide Carbo-nitride former

Nb

up to 500ppm Recrystallization control

Grain size control


Zn-pot

Time

Tem

pera

ture

Ac3

Ac1

Ms

TRIP Grades

DP Grades

QampP Grades


HDG AHSS Surface Defect Issues

801ppm P 011Mn 032Si

Bare spot defects

TRIP Steel


Surface Modification During Continuous Annealing

Decarburization

Loss volatile

alloying additions

External

selective

oxidation

Internal

selective

oxidation

Oxygen

Hydrogen

Nitrogen

uptake

Surface phase

transformation

H2O +C rarr CO + H2

H2

N2 O2

H2O

[N] [H] [O][C]

[Mn] a+g

a

[Me]

[Me]

[O]

Fe-oxide

reduction

Fe2O3

3H2 + Fe2O3

rarr 2Fe + 3H2O

H2

Normal CA-conditions

low DP ~ -30degC

pH2OpH2 oxidation potential

pH2OpH2~ 10-2 external oxidation

High pH20 internal oxidation

Mngas

xMnOSiO2

1-5

mm

H2O CO


Surface Modification During Zn Hot Dip Galvanizing

Fe and alloying

element

dissolution

Formation Fe-Zn

intermetallics

Inhibition

layer formation

Zn solidification

[Fe][Mn]

Alumino-thermia

Normal HDG-conditions

GI 02 Al

GA 014 Al

TGIGA ~465ordmC

Dipping time ~5 seconds

3MeO + 2[Al] rarr

3Me + Al2O3

Fe[Mn]

2Fe + 5[Al] + Zn

rarr Fe2Al5-xZnxz d Ghellip

Zn

Fe2Al5-xZnx Fe2Al5-xZnx Fe2Al5-xZnx

Surface defect

Zn

Fe2Al5-xZnx

Film-type

oxide


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface

embedded selective oxides

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction

Methods to Improve the CGL Galvanizability5 Selective Oxide

Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2 xMnOSiO2

Fe


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe


Selective oxide modification by DP control

Thinner surface oxide layer

Internal oxidation

Thick surface oxide layer

DP -60ordmC DP -30ordmCTransition

DP -10ordmC DP 0ordmC DP +5ordmC

1mm

0

bull Cross-sectional TEM images of the surface of a FeCMnSi TRIP steel

bull Intercritical annealing 820 oC




Internal oxidation


DP -30ordmCTransition

DP -10ordmC DP 0ordmC

1mm

0


bull Intercritical annealing 820oC

[Me]

H2Oharr H2+frac12O2

[Me]

H2Oharr H2+frac12O2

[O]


SiO2

MnOSiO2

2MnO

SiO2

SiO2

MnOSiO2

SiO2

MnOSiO2 MnOSiO2

2MnOSiO2

Factsage calculation TRIP Steel (01 C 22 Mn 14 Si) N2+10H2 820˚C


bull Effect of DP on the fraction of the oxide species on FeCMnSi TRIP steel



-60 -30 -10 0 51E-4

1E-3

001

01

1

10

100

SiO2

MnOSiO2

2MnOSiO2

Mn

Si A

tom

ic R

ati

o

Gas Atmosphere Dew Point C

MnO2

Surface oxide

Internal oxide

EDS point analysis on the surface oxides formed on CMnSi TRIP steel intercritical annealing at 820 oC


Selective oxide modification by DP control Steelcoating interface of GI TRIP steel intercritical annealing at 820 oC

10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx

DP -60 ordmC DP -10 ordmC DP +5 ordmC

Thick oxide layer

Discontinuous Inhibition layer

Thin oxide layer

Fine and continuous inhibition layer

Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer


Intercritical Annealing of a CMnSi TRIP steel (011C 153Mn 146Si)

Atmosphere DP +3C H2(10)+N2

Annealing Temperature 870C

MnO

SiO2



Al-free FeMnC TWIP Steel DP -17ordmC

Cross-sectional TEM images after annealing at 800C with N2+10H2 atmosphere



Selective oxide modification by DP control Influence of dew point on the galvanizability of medium Mn steels

Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC

6Mn 6Mn-15Si 6Mn-15Al 6Mn-15Si-15Al 6Mn-3Al


Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe


Surface modification by oxidation-reduction

Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO

Intercritical Annealing at 640 oC

EBSD analysis of the oxidation-reduction annealed medium Mn steels


Surface modification by oxidation-reduction Continuous annealing and galvanizing simulations

Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s

Hot dipping 460 oC x 4s

02Al-Zn Bath

(i) Oxidation (ii) Galvanizing

480 oC x10s

Oxidation(N2 + 01O2)

Reduction(N2 + 5H2 DP-60C)


Surface modification by oxidation-reduction Cross-sectional SEM image of oxidation-reduction annealed 6 Mn 15 Si steel

Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2


Oxidation (N2 + 01 O2) Reduction(N2 + 5 H2)



6Mn 6Mn15Si 6Mn15Al 6Mn-15Si-15Al 6Mn-3Al

Electro-polished prior to IA

Galvanizability of oxidation-reduction annealed medium Mn steels




a-Fea-Fe (FeMn)O

Al2O3

Al2O3

Mn-Al compound oxides

a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3

Cross-sectional SEM image of oxidation-reduction annealed 6 Mn 3 Al steel



Surface modification by oxidation-reduction Sealer bending test of the galvanized medium Mn steels

Area fraction of coating delamination

6Mn-15Si-15Al gt 6Mn-15Al gt 6Mn-3Al gt 6Mn-15Si gt 6Mn

6Mn-15Si 6Mn-15Al 6Mn-15Si-15Al 6Mn-3Al6Mn

Coating delaminationGood adhesive

strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2 MnOSiO2

Fe


Surface modification by Sn Bi-additions

1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm

Sn content uarr rArr formation of lens-shaped oxides

CMnSi TRIP steel intercritical annealing at 820 oC dew point -60 oC



1 mm

Reference

Mn-rich

oxides

Si-rich

oxides

Bi content uarr rArr formation of lens-shaped oxides


Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm


Surface modification by Sn Bi-additions CMnSi TRIP steel intercritical annealing at 820 oC dew point -60 oC

-Film-type

-Internal oxidation

-Lens-shaped

-No internal oxidation

Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched

layerSteel matrixSurface

oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t

Distance from the Surface nm

Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer

Surface modification by Sn Bi-additions 1 Sn added TRIP steel intercritical annealing at 820 oC dew point -60 oC



Bi soluble in liquid Zn

Bi insoluble in solid Zn

Bi insoluble solid Fe

Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]

Bi Bi BiBi Bi Bi Bi BiBi Bi Fe2Al5-xZnx

Melting T2715ordmC

Zn-bath T465ordmC

Mechanism of surface

selective oxide removal


Surface modification by Sn Bi-additions Galvanized CMnSi TRIP steel intercritical annealing at 820 oC dew point -60 oC

Sn and Bi content uarrImproved

galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeOMnO-SiO2 MnOSiO2

Fe


Selective Oxide Reduction

600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm

Thermodynamic Stability of Oxides with respect to Oxygen Partial Pressure

aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Selective Oxide ReductionCross Sectional Images of Medium Mn (6) Steel

No Mn surface oxide

No Mn surface oxide


EPMA Elemental Maps of 6 Mn SteelMn

100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide

Selective Oxide ReductionCross Sectional Images of High Mn (18)TWIP Steel


LMIE in Press Hardening

(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile

bull Zn diffusion ahead of crack tip

bull g rarr a phase transformation

bull Ferrite fracture


Coating modification in Press Hardening

100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe

Development of 55Al-Zn coating for press hardening steel

1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00Before Heat treatment

900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)

Before Heat treatment

900ordmC for 1min

900ordmC for 2min

900ordmC for 4min

55 wt Al-Zn coatingZn coating

Cathodic protection of press hardened 55Al-Zn coating

Passivation

Ecorr



LME susceptibility of 55Al-Zn coated Press hardening steel

00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s

55 wt Al-Zn coating heat treated at 900ordmC

100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl

Cracks do not propagate

beyond the diffusion layer


1 A high Al content suppresses LME

2 The coating thickness did not affect the LME susceptibility

High T tensile test Zn-32Al-16Mg coated PHS

No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions

1 Several methods are now available to control the formation

composition and morphology of the selective oxides formed during

continuous annealing prior to hot dip galvanizing

2 Compositional changes (SiMnlt2) and DP control are suitable for

intercritically annealed TRIP steel

3 Controlled oxidation-reduction leads to the formation of coating layer

porosities which may reduce the coating adhesion

4 Selective oxide reduction is a very promising approach suppressing

both the external and internal oxidation of Mn and Si

5 The methods require that some changes be made to current

continuous annealing furnace designs


Thank you

The support of the POSCO Technical Research Laboratories is gratefully acknowledged


Golf 2 (1983-1992) Golf 7 (2014)

Issue 2

Greenhouse gas emissions

Issue 1

Passenger safety

2015 130 g CO2 km rarr 2020 95 g CO2 km

2015 17 kml rarr 2020 25 kmlIssue 3

Fuel efficiency

Introduction


Properties

Processing

Microstructure


Processing

Microstructure

Performance

COST

Regulations

Steel

Unibody

Aluminum

Space frame

CFRC

Skeleton

Introduction

Al-alloy body

Steel frame


Introduction


CRS


Hot Dip Galvanised

No red rust


Zn-Fe Galvannealed

Low corrosion rate


Cosmetic corrosion



Introduction





2 Coatings issues





3 Solutions










Snout

An

nealin

g f

urn

ace

Galv

an

neali

ng

fu

rnace

Gas wipers

Zn pot

Introduction



C



Phase fractions


Si

005-15 mass-

Al

003-30 mass-

Ferrite stabilizers



Mn

15-26 mass-

5-7 mass-

15-32 mass-





Cr Mo



V



Nb


Grain size control


Zn-pot

Time

Tem

pera

ture

Ac3

Ac1

Ms

TRIP Grades

DP Grades

QampP Grades




Bare spot defects

TRIP Steel



Decarburization

Loss volatile

alloying additions

External

selective

oxidation

Internal

selective

oxidation

Oxygen

Hydrogen

Nitrogen

uptake

Surface phase

transformation

H2O +C rarr CO + H2

H2

N2 O2

H2O

[N] [H] [O][C]

[Mn] a+g

a

[Me]

[Me]

[O]

Fe-oxide

reduction

Fe2O3

3H2 + Fe2O3

rarr 2Fe + 3H2O

H2


low DP ~ -30degC




Mngas

xMnOSiO2

1-5

mm

H2O CO



Fe and alloying

element

dissolution

Formation Fe-Zn

intermetallics

Inhibition

layer formation

Zn solidification

[Fe][Mn]

Alumino-thermia


GI 02 Al

GA 014 Al

TGIGA ~465ordmC


3MeO + 2[Al] rarr

3Me + Al2O3

Fe[Mn]

2Fe + 5[Al] + Zn


Zn


Surface defect

Zn

Fe2Al5-xZnx

Film-type

oxide


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe




Internal oxidation




1mm

0






Internal oxidation




1mm

0



[Me]

H2Oharr H2+frac12O2

[Me]

H2Oharr H2+frac12O2

[O]


SiO2

MnOSiO2

2MnO

SiO2

SiO2

MnOSiO2

SiO2

MnOSiO2 MnOSiO2

2MnOSiO2






-60 -30 -10 0 51E-4

1E-3

001

01

1

10

100

SiO2

MnOSiO2

2MnOSiO2

Mn

Si A

tom

ic R

ati

o


MnO2

Surface oxide

Internal oxide




10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx


Thick oxide layer


Thin oxide layer


Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer





MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you



Properties

Processing

Microstructure


Processing

Microstructure

Performance

COST

Regulations

Steel

Unibody

Aluminum

Space frame

CFRC

Skeleton

Introduction

Al-alloy body

Steel frame


Introduction


CRS


Hot Dip Galvanised

No red rust


Zn-Fe Galvannealed

Low corrosion rate


Cosmetic corrosion



Introduction





2 Coatings issues





3 Solutions










Snout

An

nealin

g f

urn

ace

Galv

an

neali

ng

fu

rnace

Gas wipers

Zn pot

Introduction



C



Phase fractions


Si

005-15 mass-

Al

003-30 mass-

Ferrite stabilizers



Mn

15-26 mass-

5-7 mass-

15-32 mass-





Cr Mo



V



Nb


Grain size control


Zn-pot

Time

Tem

pera

ture

Ac3

Ac1

Ms

TRIP Grades

DP Grades

QampP Grades




Bare spot defects

TRIP Steel



Decarburization

Loss volatile

alloying additions

External

selective

oxidation

Internal

selective

oxidation

Oxygen

Hydrogen

Nitrogen

uptake

Surface phase

transformation

H2O +C rarr CO + H2

H2

N2 O2

H2O

[N] [H] [O][C]

[Mn] a+g

a

[Me]

[Me]

[O]

Fe-oxide

reduction

Fe2O3

3H2 + Fe2O3

rarr 2Fe + 3H2O

H2


low DP ~ -30degC




Mngas

xMnOSiO2

1-5

mm

H2O CO



Fe and alloying

element

dissolution

Formation Fe-Zn

intermetallics

Inhibition

layer formation

Zn solidification

[Fe][Mn]

Alumino-thermia


GI 02 Al

GA 014 Al

TGIGA ~465ordmC


3MeO + 2[Al] rarr

3Me + Al2O3

Fe[Mn]

2Fe + 5[Al] + Zn


Zn


Surface defect

Zn

Fe2Al5-xZnx

Film-type

oxide


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe




Internal oxidation




1mm

0






Internal oxidation




1mm

0



[Me]

H2Oharr H2+frac12O2

[Me]

H2Oharr H2+frac12O2

[O]


SiO2

MnOSiO2

2MnO

SiO2

SiO2

MnOSiO2

SiO2

MnOSiO2 MnOSiO2

2MnOSiO2






-60 -30 -10 0 51E-4

1E-3

001

01

1

10

100

SiO2

MnOSiO2

2MnOSiO2

Mn

Si A

tom

ic R

ati

o


MnO2

Surface oxide

Internal oxide




10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx


Thick oxide layer


Thin oxide layer


Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer





MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you



Introduction


CRS


Hot Dip Galvanised

No red rust


Zn-Fe Galvannealed

Low corrosion rate


Cosmetic corrosion



Introduction





2 Coatings issues





3 Solutions










Snout

An

nealin

g f

urn

ace

Galv

an

neali

ng

fu

rnace

Gas wipers

Zn pot

Introduction



C



Phase fractions


Si

005-15 mass-

Al

003-30 mass-

Ferrite stabilizers



Mn

15-26 mass-

5-7 mass-

15-32 mass-





Cr Mo



V



Nb


Grain size control


Zn-pot

Time

Tem

pera

ture

Ac3

Ac1

Ms

TRIP Grades

DP Grades

QampP Grades




Bare spot defects

TRIP Steel



Decarburization

Loss volatile

alloying additions

External

selective

oxidation

Internal

selective

oxidation

Oxygen

Hydrogen

Nitrogen

uptake

Surface phase

transformation

H2O +C rarr CO + H2

H2

N2 O2

H2O

[N] [H] [O][C]

[Mn] a+g

a

[Me]

[Me]

[O]

Fe-oxide

reduction

Fe2O3

3H2 + Fe2O3

rarr 2Fe + 3H2O

H2


low DP ~ -30degC




Mngas

xMnOSiO2

1-5

mm

H2O CO



Fe and alloying

element

dissolution

Formation Fe-Zn

intermetallics

Inhibition

layer formation

Zn solidification

[Fe][Mn]

Alumino-thermia


GI 02 Al

GA 014 Al

TGIGA ~465ordmC


3MeO + 2[Al] rarr

3Me + Al2O3

Fe[Mn]

2Fe + 5[Al] + Zn


Zn


Surface defect

Zn

Fe2Al5-xZnx

Film-type

oxide


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe




Internal oxidation




1mm

0






Internal oxidation




1mm

0



[Me]

H2Oharr H2+frac12O2

[Me]

H2Oharr H2+frac12O2

[O]


SiO2

MnOSiO2

2MnO

SiO2

SiO2

MnOSiO2

SiO2

MnOSiO2 MnOSiO2

2MnOSiO2






-60 -30 -10 0 51E-4

1E-3

001

01

1

10

100

SiO2

MnOSiO2

2MnOSiO2

Mn

Si A

tom

ic R

ati

o


MnO2

Surface oxide

Internal oxide




10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx


Thick oxide layer


Thin oxide layer


Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer





MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you



Introduction





2 Coatings issues





3 Solutions










Snout

An

nealin

g f

urn

ace

Galv

an

neali

ng

fu

rnace

Gas wipers

Zn pot

Introduction



C



Phase fractions


Si

005-15 mass-

Al

003-30 mass-

Ferrite stabilizers



Mn

15-26 mass-

5-7 mass-

15-32 mass-





Cr Mo



V



Nb


Grain size control


Zn-pot

Time

Tem

pera

ture

Ac3

Ac1

Ms

TRIP Grades

DP Grades

QampP Grades




Bare spot defects

TRIP Steel



Decarburization

Loss volatile

alloying additions

External

selective

oxidation

Internal

selective

oxidation

Oxygen

Hydrogen

Nitrogen

uptake

Surface phase

transformation

H2O +C rarr CO + H2

H2

N2 O2

H2O

[N] [H] [O][C]

[Mn] a+g

a

[Me]

[Me]

[O]

Fe-oxide

reduction

Fe2O3

3H2 + Fe2O3

rarr 2Fe + 3H2O

H2


low DP ~ -30degC




Mngas

xMnOSiO2

1-5

mm

H2O CO



Fe and alloying

element

dissolution

Formation Fe-Zn

intermetallics

Inhibition

layer formation

Zn solidification

[Fe][Mn]

Alumino-thermia


GI 02 Al

GA 014 Al

TGIGA ~465ordmC


3MeO + 2[Al] rarr

3Me + Al2O3

Fe[Mn]

2Fe + 5[Al] + Zn


Zn


Surface defect

Zn

Fe2Al5-xZnx

Film-type

oxide


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe




Internal oxidation




1mm

0






Internal oxidation




1mm

0



[Me]

H2Oharr H2+frac12O2

[Me]

H2Oharr H2+frac12O2

[O]


SiO2

MnOSiO2

2MnO

SiO2

SiO2

MnOSiO2

SiO2

MnOSiO2 MnOSiO2

2MnOSiO2






-60 -30 -10 0 51E-4

1E-3

001

01

1

10

100

SiO2

MnOSiO2

2MnOSiO2

Mn

Si A

tom

ic R

ati

o


MnO2

Surface oxide

Internal oxide




10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx


Thick oxide layer


Thin oxide layer


Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer





MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you



Snout

An

nealin

g f

urn

ace

Galv

an

neali

ng

fu

rnace

Gas wipers

Zn pot

Introduction



C



Phase fractions


Si

005-15 mass-

Al

003-30 mass-

Ferrite stabilizers



Mn

15-26 mass-

5-7 mass-

15-32 mass-





Cr Mo



V



Nb


Grain size control


Zn-pot

Time

Tem

pera

ture

Ac3

Ac1

Ms

TRIP Grades

DP Grades

QampP Grades




Bare spot defects

TRIP Steel



Decarburization

Loss volatile

alloying additions

External

selective

oxidation

Internal

selective

oxidation

Oxygen

Hydrogen

Nitrogen

uptake

Surface phase

transformation

H2O +C rarr CO + H2

H2

N2 O2

H2O

[N] [H] [O][C]

[Mn] a+g

a

[Me]

[Me]

[O]

Fe-oxide

reduction

Fe2O3

3H2 + Fe2O3

rarr 2Fe + 3H2O

H2


low DP ~ -30degC




Mngas

xMnOSiO2

1-5

mm

H2O CO



Fe and alloying

element

dissolution

Formation Fe-Zn

intermetallics

Inhibition

layer formation

Zn solidification

[Fe][Mn]

Alumino-thermia


GI 02 Al

GA 014 Al

TGIGA ~465ordmC


3MeO + 2[Al] rarr

3Me + Al2O3

Fe[Mn]

2Fe + 5[Al] + Zn


Zn


Surface defect

Zn

Fe2Al5-xZnx

Film-type

oxide


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe




Internal oxidation




1mm

0






Internal oxidation




1mm

0



[Me]

H2Oharr H2+frac12O2

[Me]

H2Oharr H2+frac12O2

[O]


SiO2

MnOSiO2

2MnO

SiO2

SiO2

MnOSiO2

SiO2

MnOSiO2 MnOSiO2

2MnOSiO2






-60 -30 -10 0 51E-4

1E-3

001

01

1

10

100

SiO2

MnOSiO2

2MnOSiO2

Mn

Si A

tom

ic R

ati

o


MnO2

Surface oxide

Internal oxide




10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx


Thick oxide layer


Thin oxide layer


Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer





MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




C



Phase fractions


Si

005-15 mass-

Al

003-30 mass-

Ferrite stabilizers



Mn

15-26 mass-

5-7 mass-

15-32 mass-





Cr Mo



V



Nb


Grain size control


Zn-pot

Time

Tem

pera

ture

Ac3

Ac1

Ms

TRIP Grades

DP Grades

QampP Grades




Bare spot defects

TRIP Steel



Decarburization

Loss volatile

alloying additions

External

selective

oxidation

Internal

selective

oxidation

Oxygen

Hydrogen

Nitrogen

uptake

Surface phase

transformation

H2O +C rarr CO + H2

H2

N2 O2

H2O

[N] [H] [O][C]

[Mn] a+g

a

[Me]

[Me]

[O]

Fe-oxide

reduction

Fe2O3

3H2 + Fe2O3

rarr 2Fe + 3H2O

H2


low DP ~ -30degC




Mngas

xMnOSiO2

1-5

mm

H2O CO



Fe and alloying

element

dissolution

Formation Fe-Zn

intermetallics

Inhibition

layer formation

Zn solidification

[Fe][Mn]

Alumino-thermia


GI 02 Al

GA 014 Al

TGIGA ~465ordmC


3MeO + 2[Al] rarr

3Me + Al2O3

Fe[Mn]

2Fe + 5[Al] + Zn


Zn


Surface defect

Zn

Fe2Al5-xZnx

Film-type

oxide


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe




Internal oxidation




1mm

0






Internal oxidation




1mm

0



[Me]

H2Oharr H2+frac12O2

[Me]

H2Oharr H2+frac12O2

[O]


SiO2

MnOSiO2

2MnO

SiO2

SiO2

MnOSiO2

SiO2

MnOSiO2 MnOSiO2

2MnOSiO2






-60 -30 -10 0 51E-4

1E-3

001

01

1

10

100

SiO2

MnOSiO2

2MnOSiO2

Mn

Si A

tom

ic R

ati

o


MnO2

Surface oxide

Internal oxide




10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx


Thick oxide layer


Thin oxide layer


Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer





MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you





Bare spot defects

TRIP Steel



Decarburization

Loss volatile

alloying additions

External

selective

oxidation

Internal

selective

oxidation

Oxygen

Hydrogen

Nitrogen

uptake

Surface phase

transformation

H2O +C rarr CO + H2

H2

N2 O2

H2O

[N] [H] [O][C]

[Mn] a+g

a

[Me]

[Me]

[O]

Fe-oxide

reduction

Fe2O3

3H2 + Fe2O3

rarr 2Fe + 3H2O

H2


low DP ~ -30degC




Mngas

xMnOSiO2

1-5

mm

H2O CO



Fe and alloying

element

dissolution

Formation Fe-Zn

intermetallics

Inhibition

layer formation

Zn solidification

[Fe][Mn]

Alumino-thermia


GI 02 Al

GA 014 Al

TGIGA ~465ordmC


3MeO + 2[Al] rarr

3Me + Al2O3

Fe[Mn]

2Fe + 5[Al] + Zn


Zn


Surface defect

Zn

Fe2Al5-xZnx

Film-type

oxide


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe




Internal oxidation




1mm

0






Internal oxidation




1mm

0



[Me]

H2Oharr H2+frac12O2

[Me]

H2Oharr H2+frac12O2

[O]


SiO2

MnOSiO2

2MnO

SiO2

SiO2

MnOSiO2

SiO2

MnOSiO2 MnOSiO2

2MnOSiO2






-60 -30 -10 0 51E-4

1E-3

001

01

1

10

100

SiO2

MnOSiO2

2MnOSiO2

Mn

Si A

tom

ic R

ati

o


MnO2

Surface oxide

Internal oxide




10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx


Thick oxide layer


Thin oxide layer


Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer





MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




Decarburization

Loss volatile

alloying additions

External

selective

oxidation

Internal

selective

oxidation

Oxygen

Hydrogen

Nitrogen

uptake

Surface phase

transformation

H2O +C rarr CO + H2

H2

N2 O2

H2O

[N] [H] [O][C]

[Mn] a+g

a

[Me]

[Me]

[O]

Fe-oxide

reduction

Fe2O3

3H2 + Fe2O3

rarr 2Fe + 3H2O

H2


low DP ~ -30degC




Mngas

xMnOSiO2

1-5

mm

H2O CO



Fe and alloying

element

dissolution

Formation Fe-Zn

intermetallics

Inhibition

layer formation

Zn solidification

[Fe][Mn]

Alumino-thermia


GI 02 Al

GA 014 Al

TGIGA ~465ordmC


3MeO + 2[Al] rarr

3Me + Al2O3

Fe[Mn]

2Fe + 5[Al] + Zn


Zn


Surface defect

Zn

Fe2Al5-xZnx

Film-type

oxide


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe




Internal oxidation




1mm

0






Internal oxidation




1mm

0



[Me]

H2Oharr H2+frac12O2

[Me]

H2Oharr H2+frac12O2

[O]


SiO2

MnOSiO2

2MnO

SiO2

SiO2

MnOSiO2

SiO2

MnOSiO2 MnOSiO2

2MnOSiO2






-60 -30 -10 0 51E-4

1E-3

001

01

1

10

100

SiO2

MnOSiO2

2MnOSiO2

Mn

Si A

tom

ic R

ati

o


MnO2

Surface oxide

Internal oxide




10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx


Thick oxide layer


Thin oxide layer


Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer





MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




Fe and alloying

element

dissolution

Formation Fe-Zn

intermetallics

Inhibition

layer formation

Zn solidification

[Fe][Mn]

Alumino-thermia


GI 02 Al

GA 014 Al

TGIGA ~465ordmC


3MeO + 2[Al] rarr

3Me + Al2O3

Fe[Mn]

2Fe + 5[Al] + Zn


Zn


Surface defect

Zn

Fe2Al5-xZnx

Film-type

oxide


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe




Internal oxidation




1mm

0






Internal oxidation




1mm

0



[Me]

H2Oharr H2+frac12O2

[Me]

H2Oharr H2+frac12O2

[O]


SiO2

MnOSiO2

2MnO

SiO2

SiO2

MnOSiO2

SiO2

MnOSiO2 MnOSiO2

2MnOSiO2






-60 -30 -10 0 51E-4

1E-3

001

01

1

10

100

SiO2

MnOSiO2

2MnOSiO2

Mn

Si A

tom

ic R

ati

o


MnO2

Surface oxide

Internal oxide




10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx


Thick oxide layer


Thin oxide layer


Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer





MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you



Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe




Internal oxidation




1mm

0






Internal oxidation




1mm

0



[Me]

H2Oharr H2+frac12O2

[Me]

H2Oharr H2+frac12O2

[O]


SiO2

MnOSiO2

2MnO

SiO2

SiO2

MnOSiO2

SiO2

MnOSiO2 MnOSiO2

2MnOSiO2






-60 -30 -10 0 51E-4

1E-3

001

01

1

10

100

SiO2

MnOSiO2

2MnOSiO2

Mn

Si A

tom

ic R

ati

o


MnO2

Surface oxide

Internal oxide




10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx


Thick oxide layer


Thin oxide layer


Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer





MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you



Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe




Internal oxidation




1mm

0






Internal oxidation




1mm

0



[Me]

H2Oharr H2+frac12O2

[Me]

H2Oharr H2+frac12O2

[O]


SiO2

MnOSiO2

2MnO

SiO2

SiO2

MnOSiO2

SiO2

MnOSiO2 MnOSiO2

2MnOSiO2






-60 -30 -10 0 51E-4

1E-3

001

01

1

10

100

SiO2

MnOSiO2

2MnOSiO2

Mn

Si A

tom

ic R

ati

o


MnO2

Surface oxide

Internal oxide




10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx


Thick oxide layer


Thin oxide layer


Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer





MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you





Internal oxidation




1mm

0






Internal oxidation




1mm

0



[Me]

H2Oharr H2+frac12O2

[Me]

H2Oharr H2+frac12O2

[O]


SiO2

MnOSiO2

2MnO

SiO2

SiO2

MnOSiO2

SiO2

MnOSiO2 MnOSiO2

2MnOSiO2






-60 -30 -10 0 51E-4

1E-3

001

01

1

10

100

SiO2

MnOSiO2

2MnOSiO2

Mn

Si A

tom

ic R

ati

o


MnO2

Surface oxide

Internal oxide




10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx


Thick oxide layer


Thin oxide layer


Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer





MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you





Internal oxidation




1mm

0



[Me]

H2Oharr H2+frac12O2

[Me]

H2Oharr H2+frac12O2

[O]


SiO2

MnOSiO2

2MnO

SiO2

SiO2

MnOSiO2

SiO2

MnOSiO2 MnOSiO2

2MnOSiO2






-60 -30 -10 0 51E-4

1E-3

001

01

1

10

100

SiO2

MnOSiO2

2MnOSiO2

Mn

Si A

tom

ic R

ati

o


MnO2

Surface oxide

Internal oxide




10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx


Thick oxide layer


Thin oxide layer


Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer





MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you



SiO2

MnOSiO2

2MnO

SiO2

SiO2

MnOSiO2

SiO2

MnOSiO2 MnOSiO2

2MnOSiO2






-60 -30 -10 0 51E-4

1E-3

001

01

1

10

100

SiO2

MnOSiO2

2MnOSiO2

Mn

Si A

tom

ic R

ati

o


MnO2

Surface oxide

Internal oxide




10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx


Thick oxide layer


Thin oxide layer


Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer





MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




-60 -30 -10 0 51E-4

1E-3

001

01

1

10

100

SiO2

MnOSiO2

2MnOSiO2

Mn

Si A

tom

ic R

ati

o


MnO2

Surface oxide

Internal oxide




10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx


Thick oxide layer


Thin oxide layer


Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer





MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




10μm

1μm

Fe-Znx

No inhibition layer

No Fe-ZnxNo Fe-Znx


Thick oxide layer


Thin oxide layer


Fe2Al5-xZnx

layer

Fe2Al5-xZnx

layer





MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you






MnO

SiO2








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you








Intercritical

annealing

temperature

-60 oC

-10 oC

0 oC

Dew Point

640 oC 700 oC 690 oC 765 oC 800 oC



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you



Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

4 Surface-active

Elements

Oxidation

control by

surface-active

elements

MnOSiO2

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Pure Fe surface


Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO

SnBiSbMnO-SiO2

Fe



Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




Oxidation

(N2 + 01O2)

Reduction

(N2 + 5H2)

111

001 101

RD

TD

111

001 101

RD

TD

FeO

a-Fe

2mm 2mm

2mm 2mm 2mm

a-Fe

MnO





Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




Tem

pera

ture

degC

Time

Intercritical

Annealing

Tgmax x 120s


02Al-Zn Bath


480 oC x10s





Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




Surface

Cross-section

FeO a-Fe + MnO

(FeMn)O

Steel

MnO

Steel

2mm

1mm

05mm

2mm

1mm

05mm

a-Fe islands

Internal SiO2











a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you










a-Fea-Fe (FeMn)O

Al2O3

Al2O3


a-Fe

(FeMn)O

Void

a-Fea-Fea-Fe

MnO

Al2O3

MnOa-Fe


Al2O3









strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you








strength


Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you



Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition

FeO-MeO


Fe



1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




1 mm

02 mm

Mn-rich

oxides

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich

oxides

1 Sn05 Sn

005 SnReference

Si-rich

oxides

Mn-rich

oxides

Si-rich

oxides

02 mm

02 mm02 mm

1 mm

1 mm1 mm





1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




1 mm

Reference

Mn-rich

oxides

Si-rich

oxides



Lens-shaped

oxides

Si-rich

oxide layers

05

Lens-shaped

oxides

Lens-shaped

oxides

Si-rich oxide

layers

02 Bi01 Bi

005 Bi

1 mm

1 mm1 mm



-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




-Film-type

-Internal oxidation

-Lens-shaped


Sn content uarr

200 nmMnO

200 nm

200 nm

200 nm

Pt Au

SiO2xMnOmiddotSiO2

xMnOmiddotSiO2

1 Sn

05 Sn

005 Sn

Reference


Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you



Surface

oxide

Sn-enriched


oxide

Fe

OSn

SiMn

0 20 40 60 80 100

01

1

10

100

Ato

mic

Per

cen

t


Fe SiMn O Sn

Steel

matrix

Sn-enriched

layer







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you







Zn

Steel

MeO[Bi]

[Bi] [Bi]

[Bi]

[Bi]


Melting T2715ordmC

Zn-bath T465ordmC






galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you





galvanizability

02Bi01Bi005Bi

1Sn05Sn005Sn

Bare spots

Reference

Poor

wetting


SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you



SnBiSb

Pure FeNi

flash coating

6 Flash

Coating

No coating

defects

Sub-surface with

internal selective

MeO oxides

2 Dew Point

Control

Pure Fe surface


4 Surface-active

Elements

Oxidation

control by

surface-active

elements

Fe-oxide and

selective MeO

oxides

3 Oxidation-

Reduction


Reduction

Reduction MeO

selective oxides

Surface

selective

oxidation

MnSi ratiogt2

1 Steel

Composition


Fe



600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




600 800 1000 1200 1400

10-50

10-40

10-30

10-20

10-10

Temperature oC

Ox

yg

enP

art

ial

Pre

ssu

re a

tm


aMe=1


2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you



2

2

2

2

800 C-10H2

800 C-10H2+10CH4

1050 C-10H2

1050 C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating


No Mn surface oxide

No Mn surface oxide



100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




100

00

Concentration

(mass)

O

30

0

Concentration

(mass)

Ave 2489 Ave 10032

1050C-10H2 Mn

100

00

Concentration

(mass)

Ave 585

O

30

0

Concentration

(mass)

Ave 0612

800C-10H2

MnO

No MnO



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you



2

2

2

2

800C-10H2

800C-10H2+10CH4

1050C-10H2

1050C-10H2+10CH4

1

1

1

1

Mn oxide

Mn oxide

Matrix

Matrix

Matrix

Matrix

Pt coating

Pt coating

Pt coating

Pt coating

Internal Al oxide

Internal Al oxide

Al nitride

External Al oxide

Al nitride

External Al oxide




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




(b)(a)

y x

z

G-Fe3Zn10a-Fe(Zn)



10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




10mm

(a) (b)

8455

407

Zn (mass)

G-Fe3Zn10a-Fe(Zn)

(c)

111

001

LME crack

A

B101

RDND

5mm

Zn

penetration

Phase

analysis

LMIE crack

profile






100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




100

000Concentration

(mass)

100

000Concentration

(mass)

50

000Concentration

(mass)

Fe2Al5

FeAl

Steel

Metallic Zn

ZnAlFe


1μm

FeAl

Fe2Al5

Zn

Zn



-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you




-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02

00

-6 -5 -4 -3 -2 -1-14

-12

-10

-08

-06

-04

-02


900ordmC for 1min

900ordmC for 3min

E

V (

SC

E)

Log I A cm-2

Uncoated PHS

Log I A cm-2

E

V (

SC

E)


900ordmC for 1min

900ordmC for 2min

900ordmC for 4min



Passivation

Ecorr




00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you





00 01 02 03 040

20

40

60

80

100

120

140

En

g

Str

ess

[M

Pa

]

Eng Strain

Soaking for 1min

Soaking for 4min

Soaking for 2min

Strain rate 05 s


100

000

Concentration

(mass)

100

000Concentration

(mass)

60

000Concentration

(mass)

Soaking for 4min

10μm

Fe

ZnAl







No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you






No LME

En

g S

tress

[MP

a]

Eng Strain

00 01 02 03 040

20

40

60

80

100

120

140

104g

58g

32g

Zn-16Al-16Mg_32g

Zn-16Al-16Mg_104g

Zn-16Al-16Mg_58g


Conclusions













Thank you



Conclusions













Thank you



Thank you


IUMRS-ICAM 2015_Selective Oxidation AHSS and UHSS_OCT 25-29_2015

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Transcript of IUMRS-ICAM 2015_Selective Oxidation AHSS and UHSS_OCT 25-29_2015