Reduction in Friction in Ironing of Aluminium Alloy and...

Reduction in Friction in Ironing of

Aluminium Alloy and Stainless Steel Drawn Cups

Name : Witthaya Daodon

Nationality : Thailand

Educational background

Year Institution Qualification

1998-2000Rajamangala University of Technology

Diploma of Machine Tools Technology

2000-2003King Mongkut’s University of Technology Thonburi

Bachelor of Engineering

2009-2012King Mongkut’s University of Technology Thonburi

Master of Engineering

Working experiences

Year Company Position

2003-2004 Thai Ahresty Die Co., Ltd. CAD/CAM engineer

2004-2005Honda Automobile (Thailand) Co., Ltd.

Machining staff

2006-2008 Siam Lemmerz Co., Ltd. Design engineer

2008-2009 Sunway E-Systems (Thailand) Ltd.

Application engineer1

Chapter Contents

1 Introduction

2Ironing of stainless steel and aluminium alloy drawn cup using

TiCN-based cermet die

3Reduction in friction in ironing of stainless steel and aluminium

alloy drawn cup using die having lubricant pockets

4Lubrication behaviours in ironing of stainless steel cup with die

having lubricant pockets

5Improvement of lubrication in ironing of stainless steel cup by

surface roughening

6Lubricant containing fine particles for improving seizure

resistance in ironing of aluminium alloy cup

7Improvement of seizure resistance in ironing of aluminium alloy

cup using titanium nitride coated die

8 Concluding remarks

Reduction in Friction in Ironing of Aluminium Alloy

and Stainless Steel Drawn Cups

2

Electric vehicles

Battery weight,

20-25%wt of car

Battery case

Battery pack for electric car

Stainless steel

Aluminium alloy

Environmental protection

Electric, hybrid, plug-in hybrid

vehicles

Reduction of CO2emission

Key component,

Battery

Weight Efficiency

3

Blank

Cup

(a) Multi-stage stamping

(b) Impact extrusion

Battery case production processes

Redrawing

Deep drawing

die

Punch

Blank holder

Deep drawing

Ironing die

Ironing

High contact pressure

Large deformation,Long sliding

Punch

Billet

Die

Seizure

Stainless steel

High strength

Low thermal

conductivity

Aluminium alloy

High adhesion

Low friction tool

materials

Lubrication

Coating

Reduction in friction

4

Chapter Contents

1 Introduction








surface roughening








5

Ironing of stainless steel and aluminium alloy

drawn cup using TiCN-based cermet die

A TiCN-based cermet die was utilised to improve the limit in ironing of

stainless steel and aluminium alloy drawn cups.

1mm

SeizureIroning dieH

ard

ness /

HV

Coefficient of friction

Tool steel DIN 1.2379(JIS SKD11)

CrN

TiC

TiCN

TiN

CVD-coatingsPVD-coatings

WC/C

MoS2

3000

2000

1000

4000

0.6 0.80.40.200

SeizureIroned cup

Tool steel

Hardness: low

Friction: high

Seizure resistance: low

TiCN-based cermet

Hardness: high, Friction: low

Seizure resistance: high

6

Ironing conditions and die materials

Die materials Young’s modulus [GPa] Vickers hardness [HV]

Tool steel SKD11 206 750

Non-coated WC-Co 610 1650

TiC-coated WC-Co 610 1650, 3000(TiC)

TiCN-based cermet 410 1550

1mm

(a)Tool steel

Circumferential

Axia

l

RingDie Sintering

Lubricant

Drawn cup;

SUS304,

SUS430

A3003-O

dp

Punch

c

f 34

Die

v=100mm/s

Ring

7

Ironing load-stroke curve for SUS304

with different tool materials, dp=33.16 mm

10

20

30

40

50

60

0 10 20 30

70

Stroke [mm]40

80

90Non-coated WC-Co, r=16%

TiC-coated WC-Co, r=14%

8

Ironing limit, surface of die land and ironed cups

for stainless steels with different tool materials

0

10

20

Ironin

g r

atio r

[%]

Fracture

No defectSeizure

Seizure and fracture

No seizure1mmSeizure

Non-coated WC-Co

10mm 0.5mm

Die

0

10

20

25

Ironin

g r

atio r

[%]

1mm

No defect

Seizure

(a) SUS304 (b) SUS430 9

Ironing limit for A3003 cup with different tool materials

1mm

0

10

20

30

40

No defect

Seizure

Ironin

g r

atio r

/%

Seizure

Tool steel Non-coated WC-Co

TiC-Coated WC-Co

Seizure and fracture in edge

Fracture in edgePortion of observation

Ironing die

10

Before ironing

Tool steel

30.8

30.3

TiC-coated WC-Co

32.9

32.1

(a) Ironed SUS304 cups

Young’s modulus: largeExpansion: small

Height: tall

Reduction in thickness: large

Thin wall

Young’s modulus: smallExpansion: large

Height: short

Reduction in thickness: small

Thick wall

Expansion of die

Die

Punch

Ring

Clearance

(b) Expansion of die 11

Effect of Young’s modulus of die

on height and sidewall thickness of ironed cup

Su

rfa

ce

ro

ugh

ne

ss [

mm

Ra]

Number of strikes n

Blank

0

0.02

0.04

0.06

0.08

0.10

0.12

20 40 60 80 100

SUS430,TiC-coated WC-Co

A3003,TiC-coated WC-Co

SeizureTiC-coated WC-Co

Punch

Deep drawing

die

Ring

Ironing die

Ironed cup and variation of surface roughness

of ironed cups in repeated ironing

Repeated ironing

12

Conclusions

The limits in ironing of stainless steel and aluminiumalloy drawn cups were effectively improved by using theTiCN-based cermet die.

The height of ironed stainless steel cups with the TiC-coated WC-Co die was the highest and followed by theTiCN-based cermet die.

For repeated ironing of the ferritic stainless steelSUS430 and aluminium alloy A3003 cups using theTiCN-based cermet die, the cups were successfullyformed up to 100 and 50 strokes.

1.

2.

3.

13

Chapter Contents

1 Introduction








surface roughening








14

Die having lubricant pockets

(a) Polished

Polished surface

Cup Die

Lubricant

Cup

Die

The TiCN-based cermet die having fine lubricant pockets was utilised to

reduce friction in ironing of stainless steel and aluminium alloy drawn cups.

(b) Die having lubricant pockets

Ironed cups

Reduction in friction in ironing of stainless steel and

aluminium alloy drawn cup using die having lubricant pockets

Punch

Ironing

die

Cup

Liquid lubricant

15

Ironing conditions

Material: TiCN-based cermet

Surface:

• Polished (0.02μmRa)

• Surface having lubricant pockets

(0.03~0.21μmRa)

• Shot-peened (0.05~0.34μmRa)

Ironing dieLubricant

Drawn cup;

SUS304,

SUS430,

A3003-O

dp

Punch

c

f 34

Die

Ironing speed;

v=100mm/s

Ring

Sheet Tensile strength [MPa] Elongation [%] n-value r-value

SUS304 710 59.3 0.40 1.01

SUS430 547 25.7 0.20 1.17

A3003 106 26.8 0.21 0.42

16

0.05µmRa, 0.02µmRpk, 0.18µmRvk


(b) Shot-peened

-2

0

Position in axial direction /µmH

eig

ht

/µm 1

-1

0 200 400100 3000.1mm

(a) Polished, 0.02µmRa, 0.01µmRpk, 0.06µmRvk

(c) Surface having lubricant pockets



Surface shapes of die land

17

Effect of die land surface on ironing limit for SUS430 cup

(a) Shot-peened (b) Die having lubricant pockets

Iro

nin

g r

atio

r/%

30

20

10

00.40.2 0.30.1

25

15

5

35

Reduced valley depth in land portion of die /µmRvk0.5

Seizure

Fracture

No defect

Seizure

0.4

0

0.1

0.3

0.2

Re

du

ce

d p

ea

k h

eig

ht in

la

nd

p

ort

ion

of d

ie /µ

mR

pk

Po

lish

ed

Rpk

Ironing die

0.1mm

Fracture Seizure

0.2mm

Large pockets

Flat portion

18

Ironing limit for die having lubricant pockets and

A3003 cups

Iro

nin

g r

atio

r/% 30

20

10

00.40.2 0.30.1

25

15

5

35

0.5

0.4

0

0.1

0.3

0.2

Polished

40

45

Fracture

Seizure

10mm

0.5

No defect

Re

du

ce

d p

ea

k h

eig

ht in

la

nd

po

rtio

n o

f d

ie

/µm

Rp

k

Reduced valley depth in land portion of die /µmRvk

Rpk

19

Relationship between average ironing load and

ironing ratio for SUS430 cups

30

20

10

40

10 15 20 25 305

Ave

rag

e iro

nin

g lo

ad

/kN

Polished (0.02µmRa)

Die having lubricant pockets,

0.03µmRa~0.15µmRa

0

Shot-peened,

0.06µmRa~0.14µmRa

Ironing ratio r /%

20

Conclusions

1. The ironing limit with the die having lubricant pockets forthe reduced valley depth of 0.22 µm to 0.42 µm wasimproved.

2. The reduced peak height was more than 0.06 µm, thedefect early occurred at a low ironing ratio.

3. The average ironing load of SUS430 cup with the diehaving lubricant pockets was reduced about 20%compared to the polished die.

21

Chapter Contents

1 Introduction








surface roughening








22


The conditions of the ironing process and lubrication for attaining low friction

in ironing of stainless steel cups using the cermet die having fine lubricant

pockets were investigated.

Lubrication behaviours in ironing of stainless steel cup

with die having lubricant pockets

During ironing

Enhanced lubrication

Measurement of thickness of remaining lubricant

DieLamp

Camera

l

t

Glass Fluorescence oil-mixed lubricant

Steel ball

Die

Ultraviolet rayslamp

Camera

PunchRemaininglubricant

State of lubrication,Conditions for reducing friction

Ultraviolet rays lampLubricant

+Fluorescence oil, 1wt%

23

Cup

Die

Distribution of thickness of remaining lubricant on

sidewall of ironed cup for v=100 mm/s

zDistance from bottom of ironed cup z /mm

0

5

10

15

20

5 10 15 20 25

25

30

Thic

kness o

f re

main

ing lubricant

/μm

Corner Sidewall

30

Polished, Chlorine, r=12.8%

Reflection of ultraviolet lights

10mm

Measuring position

Die having lubricant pockets, Sulfur, r=5.7%

Polished, Sulfur, r=5.5%

Die having lubricant pockets, Chlorine, r=13.7%

24

Effect of extreme-pressure additives on ironing limit

for v=100mm/s

10mm

Iro

nin

g r

atio

r/%

(b) Chlorine

0

20

10

30

No defect

Fracture

0.1mm

Seizure

(a) Sulfur

0

20

10

Iro

nin

g r

atio

r/% Seizure

0.1mm

No defect

Portion of observation

Ironing die

25

Effect of ironing speed on ironing limit and thickness

of remaining lubricant on sidewall of ironed cup

with lubricant containing chlorine additive

Iro

nin

g r

atio

r /%

(i) Die having lubricant

pockets

0100 15050

20

10

30

Ironing speed v /mm·s-1

No defect

Fracture

(ii) Polished

0 50 100 150

No defect

Seizure

(a) Ironing limit

Polished, r=13%

Die having lubricant pockets,

r=25%

Th

ickn

ess o

f re

ma

inin

g

lub

rica

nt /μ

m

Ironing speed v /mm·s-1

4

050 100 150

2

1

3

5

6

b) Thickness of remaining lubricant on sidewall of ironed cup 26

Cup

Die

0.1mm

No seizure

Ave

rag

e iro

nin

g lo

ad

/kN

Amount of applied lubricant /µg·mm-2

30

0

10

20

40

37030 4515


Seizure

Polished

Th

ickn

ess o

f re

ma

inin

g

lub

rica

nt /μ

m


Polished

3

0

1

2

37030 4515

Seizure

Effect of amount of applied lubricant on seizure limit

and thickness of remaining lubricant with lubricant

containing chlorine additive for v=100mm/s and r=13%

(a) Seizure limit b) Thickness of remaining lubricant on sidewall of ironed cup 27

Su

rfa

ce

ro

ug

hn

ess o

f iro

ne

d

cu

p /μ

mR

a

0.1mm

Number of strikes n

0

0.50

0.20

0.10

0.40

0.30

Severe seizure

Mild seizure

Mild seizure

15050 100 250200 300

Blank

Polished


25

(a) Die having lubricant pocketsn=10 n=300

(b) Polished

Fracture

Seizure

0.1mm

n=10 n=150

10mm

Ironed cup and variation of surface roughness

of ironed cups in repeated ironing

Punch

Deepdrawing

Ironing

Repeated ironing

28

Conclusions

1. For the die having lubricant pockets, the sufficientamount of the lubricant and the high ironing speed werethe better condition for reducing friction.

2. The film thickness of the remaining lubricant with the diehaving lubricant pockets was thicker than that with thepolished die.

3. In repeated ironing, the surface roughness of ironedcups maintained the same level regardless of thenumber of strikes for the die having lubricant pockets.

29

Chapter Contents

1 Introduction








surface roughening








30

b) Die havinglubricant pockets

c) Rougheningsurface of cup

Trapped lubricant

Large trapped lubricant

IroningSqueezed

out lubricantDuring ironing

Die

Lubricant

Cup

Before

a) Polished die Axial CircumferentialFineRough

d) Sanding

Rough

e) Deep drawingwith large clearance

Large clearance

Small radius

f) Two-stage deepdrawing

Improvement of lubrication in ironing of

stainless steel cup by surface roughening

Surface roughening of drawn cups was utilised to improve lubrication in

ironing of stainless steel cup. 31

Effect of sanding direction of cup on ironing load-stroke

curve for lubricant containing sulphur additive

Axial sanding with #80,Rz=0.35µmRa, r =11.4%

20

40

Stroke /mm

Iro

nin

g lo

ad

/kN

0 5 10 15 20 25 30

10

30

50

Circumferential sanding with #80,Rz=0.60µmRa, r =12.1%

32

Lubricant squeezed out

Lubricant trapped

(a) Axial sanding

(b) Circumferential

sanding

Effect of arithmetic mean surface roughness of cup on

ironing limit for lubricant containing sulphur additive

Surface roughness of cup in axial direction Rz /μmRa

Iro

nin

g r

atio

r /%

0.60.40.2 0.3 0.50.1

30

20

10

0

Seizure

No defect

Drawn cup with chorine additives

(a) Polished (0.02μmRa)

0.1mm

Circumferential

sanding with #1500

Circumferential

sanding with #80Drawn cup

0 0.40.2 0.3 0.50.1 0.6

No defectSeizure

(b) Die having fine lubricant pockets

(0.06μmRa)

Drawn cup with chorine additives

Axial sanding with #80

33

Ironing limit for cups formed by deep drawing with

large clearance and two-stage deep drawing

cd=100%, chlorine additives

No defect

30

20

10

Seizure andfracture

Iro

nin

g r

atio

r/%

Seizure

Seizure

0.1mm

cd=100%, sulphur additives

Deep drawing with large clearance,

cd=120%, Rz=0.43μmRa

Two-stage deep drawing including

deep drawing and redrawing with

small die radius, Rz=0.57μmRa

Large clearance

Small radius

34

Relationship between coefficient of friction in ironing

and ironing ratio

10 15 20 255

Ironing ratio r /%

0.16

0.12

0.08

0.04

0

Co

effic

ien

t o

f fr

ictio

n

Circumferential sanding with #80, Rz=0.60μmRa

Drawn cup, Rz=0.30μmRaDeep drawing with large clearance, cd =120%, Rz=0.43μmRaRedrawn cup, Rz=0.57μmRa

35

Effect of surface roughness of drawn cup on

average thickness of remaining lubricant

0.3 0.40.20.1 0.50 0.6 0.7

0.5

1.0

1.5

2.0

Surface roughness in axial direction of cup Rz /μmRa

Ave

rag

e th

ickn

ess o

f lu

bri

ca

nt film

in

sid

ew

all

fro

m 1

5m

m to

30

mm

/μ

m

Drawn cup,0.30μmRa

Deep drawing with large clearance, cd=120%,

0.43μmRa

Circumferentialsanding with#80, 0.60μmRa

Redrawing,0.57μmRa Cup

Die

Enhanced lubrication

15~30

36

Conclusions

1. The ironing limit with the cup sanded in thecircumferential direction was higher than with the cupsanded in the axial direction.

2. Friction in ironing was reduced by roughening of cupsurface because of the improvement of lubrication.

3. The thickness of the remaining lubricant on the sidewallof the ironed cup increased as the surface roughness inthe axial direction of the drawn cup increased.

37

Chapter Contents

1 Introduction








surface roughening








38

Lubricant containing fine particles for improving

seizure resistance in ironing of aluminium alloy cup

The lubricant containing fine particles was applied to improve

the seizure resistance in ironing of aluminium alloy cups.

Fine SiO2 particles,

0.01µm

Metal cutting,

sliding bearing

Lubricant

SiO2particle

Cup

Die

Seizure

(a) Lubricant without particles

(b) Lubricant with particles

Machining process

Tool

Workpiece

Fine SiO2particles

Prevention of contact

Cutting oil

Aluminium alloy,

high adhesion

39

Ironing conditions by lubricant containing fine particles

Drawn cup;

A3003-Odp

Punch

c

f 34

100mm/s

Ring

Lubricant+fine particles

W=0~5wt%(0~2vol%)

Die,Polished

Particles Hardness /HV Density /g·cm-3Average particle size ds/nm

SiO2 950 2.2 10, 300 and 500

ZrO2 1230 5.68 13

Al2O3 1570 3.95 15

Material properties of fine particles

Lubricant

Paraffin oil,

Kinematic viscosity

v= 10 and 500 mm2/s

A3003-O: 31 HV, TiCN-based cermet: 1550 HV

40

Effect of types of fine particles mixed in lubricant on

seizure resistance for ν=10 mm2/s, W=1wt%

Fine particles

SiO2 ZrO2

Ironing limit of lubricant without particlesIr

on

ing

ra

tio

r /%

0

20

10

30

40

Al2O3

No defect

Seizure

0.1mm

Seizure

41

Effect of size of fine SiO2 particles mixed in

lubricant on ironing limit and average ironing load

for ν=10 mm2/s and W=5wt%

(a) Ironing limit and surface of die land (b) Average ironing load

for r=23%

Size of particles ds [µm]A

ve

rag

e iro

nin

g lo

ad

[kN

]

0.0

1µ

m

0

4

2

6

0.5

µm

0.3

µm

With

ou

t p

art

icle

Size of particles ds [µm]0.1 0.40.2 0.3

Ironing limit of lubricant without particles

Iro

nin

g r

atio

r [%

]

0

20

10

30

0.1mm

40

0.5

No defect

No defect


Ring

Ironing die


Seizure

42

Effect of quantity of fine SiO2 particles mixed in

lubricants on ironing limit for ds=0.01μm

Mixing quantity of SiO2 W [wt%]1 2 301 542 3


(a) ν =10 mm2/s (b) ν =500 mm2/s

No defect

Seizure


Iro

nin

g r

atio

r [%

]

0

20

10

30

40

No defect


Seizure


Ironing die0.1mm

No defect

0.1mm

Seizure

43

SEM observation and quantification of Si element on

sidewall of ironed cup

ν =10 mm2/s

Mixing quantity of SiO2 W /wt%1 542 3

Qu

an

tifica

tio

n o

f S

i

ele

me

nt /w

t%

0

0.4

0.2

0.6

ν =500 mm2/s

20

Analysedportion

(i) W=0%, r =24.2% (ii) W =1wt%，r =34.8%

10μm

(a) SEM images on ironed cup surfaces, ν=500 mm2/s

(b) Quantification of Si element on sidewall of ironed cup 44

Conclusions

1. Seizure resistance in ironing of the aluminium alloy cupswas improved with the lubricant containing fine SiO2particles having size of 0.01 µm.

2. For ZrO2 or Al2O3 particles, seizure resistance wasequal to or inferior to the lubricant without fine particles.

3. Seizure resistance was effectively improved by applyingthe high viscosity lubricant with fine SiO2 particles.

45

Chapter Contents

1 Introduction








surface roughening








46

TiN and VN coatings deposited by a direct current (DC) magnetron

sputtering PVD were utilised to improve seizure resistance in ironing of

aluminium alloy cups.

Uncoated high-speed steel die

Hardness: lowFriction: highSeizure resistance: low

Improvement of seizure resistance in ironing of

aluminium alloy cup using titanium nitride coated die

Coated high-speed steel dieHardness: Friction:

Seizure resistance:

Ironing die Seizure

1mm

Ironed cup

Low surface quality

Physical vapor deposition: PVD

DC magnetron

sputtering technique

Cathodic arc

technique

SKH51

Smooth

Coating

Rough

47

Surface roughness of coated discs

Before coating

After coating

Uncoated Cathodic arc TiN

225W-TiN 265W-TiN 225W-VN 265W-VN

Surf

ace r

oughness [

µm

Ra]

0

0.010

0.005

0.015

0.020

Coatings

0.025

48

Coatings

Load-t

o-f

ailu

re

[N]

0

20

40

60

80

(b) Load-to-failure of discs

Hardness and load-to-failure of coated discs

(a) Hardness of discs

Hard

ness [

HV

]

0

500

1000

1500

2500

2000

Coatings

3000

Aluminium adherence index of coated discs

in ring-on-disc test

Al adhere

nce inde

x

0

0.05

0.10

0.15

Coatings

0.20

Uncoated 225W-TiN500µm

Load

Ring-on-disc test

500µm

Aluminium Aluminium

AA1050 H14

SKH51

50

Surface roughness of ironed cups

Su

rfa

ce

ro

ug

hn

ess o

f

ironed c

up [μ

mR

a]

0

0.4

0.2

0.6

0.8

Number of strikes n

4020 3010 6050

Uncoated die

225W-TiN-coated die

Drawn cup

225W-TiN, n=10Uncoated, n=10

100µm

Severe seizure Small seizurePunch

(SKD11) Die (SKH51)

Drawn cupAA1050 H14

Ring

f 39.75

5

f 39.10

100mm/s

51

Conclusions

1. Cathodic arc TiN coating exhibited the highest hardnessand had the highest ability to resist cracking.

2. All of the coatings were effective in reducing aluminiumtransferred to the discs.

3. The 225W-TiN coating with a low degree of aluminiumtransfer performed well in ironing.

52

Chapter Contents

1 Introduction








surface roughening








53

Future perspectives

Die having lubricant pockets + chlorine additive

Cup

Die

Enhancement, boundary lubrications

Suitable application for several

work materials, different

additives

Particles Hardness /HV Density /g·cm-3

SiO2 950 2.2

ZrO2 1230 5.68

Al2O3 1570 3.95

ZnO 418 5.61

CuO 229 6.14

A3003-O: 31HV, SKD11: 750HV, TiCN-based cermet: 1550HV

Lubricant + fine particles

54

SiO2 , lower hardness, well perform

List of publications and conference

1. 安部洋平，森謙一郎，畑下文裕，柴孝志，Witthaya Daodon，“潤滑剤ポケットを有する

ダイを用いたステンレス鋼容器のしごき加工における耐焼付き性の向上－潤滑剤ポケットを有するサーメットダイを用いたしごき加工第1報－”，塑性と加工，56-658 (2015), 972-978.

2. Witthaya Daodon，安部洋平，森謙一郎，高橋尚志，“潤滑剤ポケットを有するダイを用

いたステンレス鋼容器のしごき加工における最適潤滑条件－潤滑剤ポケットを有するサーメットダイを用いたしごき加工第2報－”，塑性と加工，57-660 (2016), 22-27.

3. Witthaya Daodon, Varunee Premanond, Witthawat Wongpisarn, Panadda

Niranatlumpong, “Vanadium nitride and titanium nitride coatings for anti-galling

behavior in ironing of aluminum alloy cups”, Wear 342-343 (2015), 279-287.

4. C.J. Tan, Y. Abe, W. Daodon, N. Takahashi, K. Mori, J. Purbolaksono, “Increase in

ironing limit of aluminium alloy cups with lubricants containing nanoparticles”,

Journal of Materials Processing Technology, 229 (2016), 804-813.

1. Yohei Abe, Tomohiro Fujita, Ken-ichiro Mori, Kozo Osakada, Takashi Shiba and

Witthaya Daodon, “Improvement of formability in ironing of stainless steel drawn

cups using low friction cermet dies”. 11th International Conference on Technology of

Plasticity, October 19-24, 2014, Nagoya, Japan.

2. Witthaya Daodon, Yohei Abe, Ken-ichiro Mori and Shingo Kato, “Improvement of

seizure resistance in cold extrusion of alminium alloy billet using die having

heterogeneous surface”. 7th JSTP International Seminar on Precision Forging, March

9-12, 2015, Nagoya, Japan. 55

Reduction in Friction in Ironing of Aluminium Alloy and...

Documents

Transcript of Reduction in Friction in Ironing of Aluminium Alloy and...