Lithium Disilicate Glass-ceramics for dental applicationsocw.snu.ac.kr/sites/default/files/NOTE/01a....

Electronic Materials & Devices LaboratorySeoul National UniversityDepartment of Material Science & Engineering

Lithium Disilicate Glass-ceramics

for dental applications

March, 14, 2016

Department of Materials Science and Engineering,

Seoul National University

Supervisor : Prof. Sang-Im Yoo

Dami KIM

Seoul National UniversityDepartment of Material Science & EngineeringElectronic Materials & Devices Laboratory

2/40Contents

1. Introduction

2. Research Subtopics

I-1. Crytallization of lithium disilicate glass-ceramics by mixture design

I-2. Effect of crystallization on mechanical properties of lithium disilicate

glass ceramics

I-3. Effect of the colorants on the color and translucency of lithium

disilicate glass-ceramics


3/40

3

Posterior teethAnterior teeth

Introduction : Properties of Human teeth

<Color of human tooth>

L* a* b*

66.2± 3.6 2.6±1 14.4±3.9

<Translucency of human tooth>

Ref) Rubino, M et al, Color Research & Application 19 (1994) 19-22

<Toughness & Hardness of human teeth>

http://www.glidewelldental.com/images/dentist/chairside/v7-4/articles/zirconia-veneer/lightbox/Fig18.jpg

Enamel : Blue/White Opalesence & Fluorescence

GPa5.4

m MPa5.4 1/2

≈

≈

Ref (https://en.wikipedia.org/wiki/Tooth_enamel

Ref) V.Imbeni, Nature. Mat. 4 (2005) Ref) Yong-Keun Lee, J. Biomed. Opt 20(4)


4/40

4

Introduction : Dental Materials

Amalgam

Metal crown

Fracture occured (Porcelain : 75~100MPa)PFM(Porcelain Fused metal) crown

All-ceramic crown


5/40

5

<Translucency>

<Dental Implant>

Single crown 3-unit Bridge

Introduction : Dental ceramics

0

200

400

600

800

1000

1200

1400

Leucite GC

(IPS Empress)

Lithium Disilicate

(IPS e.max)

Alumina

(Procera)

Zirconia

(Lava)Fl

exu

ral st

rength

(M

Pa)

• High strength

• Moderate hardness

• Excellent esthetics

- Shade(color)

- Translucency


6/40

6

Introduction : Manufacturing of Crown

<Hot-Pressing : LS2 GC> <CAD/CAM : Zirconia, Alumina, LS GC>

Zironia block

LS2 Ingot

Plastic deformation of

LS2 GC (softening)

Hot-pressing furnace


7/40

7

Introduction : Lithium disilicate glass-ceramics

21%

18%

13%9%8%

6%4%

21%

Companies of Crowns and Bridge

Ivoclar Vivadent AG Noritake Co., Limited

Dentsply International Inc. SHOFU INC.

3M ESPE Dental Products Nobel Biocare Holding AG

VITA In-Ceram Others

Benchmarking!

Shade (color) Translucency


8/40

8

Optimal crystallization condition Shade & TranslucencyPlastic deformation (Softening)

Manufacturing condition

Part. I

To obtain optimal crystallization condition for LS2 GC by design of composition through mixture design.

To identify the appropriate heat-treatment condition.

Part. II Part. III

To fit the shade and

translucency of

Benchmarking product.

(Ivoclar vivadent)

To study about plastic

deformation behavior

of LS2 GC for hot-

pressing condition.

Motivation & Objective

Development of suitable composition design and estabilishment of heat-treatment

condition to obtain 400MPa flexural strength of lithium disilicate glass-ceramics with

various color, translucency and feasibility of plastic deformation.


9/40

I-1. Crytallization of Lithium Disilicate

Glass-Ceramics by Mixture Design


10/40

10

Part I-1. Motivation & Objective

Roles Additives Details

Nucleation

reagent

P2O5Bulk Crystallization

ZrO2Additives for mechanical strength

TiO2Surface Crystallization

Pt, Pd, Au, Ag Surface/bulk Crystallization

Glass

network

Former

&

Modifier

K2O flux

Na2O flux

BaOIncrease of Li2SiO3 crystallization peak

although lead to decrease of Volume fractionCaO

Viscosity

&

chemical

stability

La2O3 ,Al2O3control viscosity and flow in plastic state

MgO, ZnO,

Nb2O3 ,B2O3,

SrO

• Good chemical stability

• Low viscosity to enhance Li2SiO3 crystal

result in moderate fraction

• Deteriorate crystal growth of Li2SiO5

<Additives for LS2><Crystallization of Lithium Disilicate(LS2) Glass>

Ref) Glass and Glass Ceramics for Medical Applications (Emad El-Meliegy) p212~214

RT

G

aN

fRTU exp1

3 2

0

On the basis of mixture design (Design of experimental), the effect of

additives ratio on crystallization of LS2(Li2O∙2SiO2) was studied.

kT

GWAI D )(

exp*

Liquid-liquid phase separation


11/40

Additives P2O5 ZnO K2O

Raw materials (NH4)2HPO4 ZnO K2CO3

Role Nucleation agent Glass modifier

• Matrix SiO2/Li2O=2.3 (94mol% fixed)

• Total amount of additives : 6mol%

<Glass composition>

Experimental

0 20 40 60 80 100

0

20

40

60

80

1000

20

40

60

80

100

131211

109876

5432

ZnO

P2O

5

K2O

1

0

200

400

600

800

1000

1200

1400

1600

NucleationAnnealing

Forming

Crystallizaion

Te

mp

era

ture

(oC

)

Time (min)

Melting

Glass fabrication :

Melt-Quenching method

<Experimental>

<Bi-axial strength>

• ISO 6872

• Piston on a 3-balls

• Sample size : 12.8mm(Dia), 1.2T

<Hardness : Vicker’s >

• Indentation load: HV 0.5

• Duration time : 10s

Sample ID

Compositions of

additives (mol%) ZnO/K2O

P2O5 K2O ZnO

#1 1.5 3 1.5 0.5

#2 1.5 2.25 2.25 1

#3 1.5 1.5 3 2

#4 1.25 2.75 2 0.727

#5 1.25 2 2.75 1.375

#6 1 3 2 0.667

#7 1 2.5 2.5 1

#8 1 2 3 1.5

#9 0.75 2.75 2.5 0.909

#10 0.75 2.5 2.75 1.1

#11 0.5 3 2.5 0.833

#12 0.5 2.75 2.75 1

#13 0.5 2.5 3 1.2


12/40

12

XRD

10 20 30 40 50

13

12

11

10

Inte

nsity (

a.u

.)

2-theta (2)

9

10 20 30 40 50

6

4

8

5

7

3

2

Inte

nsity (

a.u

.)

2-theta (2)

1

Lithium Disilicate [01-072-0102]

Cristobalite – SiO2 [01-071-0785]

0 20 40 60 80 100

0

20

40

60

80

1000

20

40

60

80

100

131211

109876

5432

ZnO

P2O

5

K2O

1

CompositionP2O5 ZnO/K2O(mol%)

1

1.5

0.5

2 1

3 2

41.25

0.73

5 1.38

61

0.67

7 1

8 1.5

90.75

0.9

10 1.1

110.5

0.83

12 1

13 1.2

• The formation of secondary phase cristobalite is thought to

be related to the Zn2+ ion

• The Zn2+ is thought to be located at tetrahedral sites since it

prefers four coordination due to strong covalent boding via

sp3 hybridization

• It is assumed that Zn2+ ions behave as a glass former in the

tetrahedral unit (ZnO4)2- possessing Li+ and K+ to maintain

neutrality in the glass, and therefore the Si-rich region

increases near (ZnO4)2- and is crystallized as cristobalite.

Nucleation agent


13/40Microstructure : SEM

0 20 40 60 80 100

0

20

40

60

80

1000

20

40

60

80

100

131211

109876

5432

ZnO

P2O

5

K2O

1

Nucleation agent

0.4 0.8 1.2 1.6 2.00

1

2

3

4 P

2O

5 1.5mol%

P2O

5 1.25mol%

P2O

5 1mol%

Length

ZnO/K2O

0.4 0.8 1.2 1.6 2.01.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

P2O

5 1.5mol%

P2O

5 1.25mol%

P2O

5 1mol%

Aspect ra

tio

ZnO/K2O

Spherulite


14/40

14

Strength & Hardness

13121110987654321

6.5

6.0

5.5

5.0

4.5

4.0

3.5

3.0

Vic

ker'

s h

ard

ness (

GPa)

0 20 40 60 80 100

0

20

40

60

80

1000

20

40

60

80

100

131211

109876

5432

ZnO

P2O

5

K2O

1

Nucleation agent

13121110987654321

450

400

350

300

250

200

150

100

50

Bi-

axia

l strength

(M

Pa)

ZnO ↑

ZnO ↑

• The Bi-axial strength and hardness increased as increase of P2O5.

• The hardness tend to increase by increase of ZnO.

• The strength and hardness prone to increase as decrease of grain

size. It is thought that the addition of P2O5 provided many sites

of crystalline phase, and the ZnO hinderd the growth of LS2

phase by consuming Li+ Ion.

P2O5 ↑ P2O5 ↑


15/40

15

Surmmary

15

The crystal size became small as increase of P2O5 due to its increase of

heterogeneous nucleation sites and more spherical as increase of ZnO.

The ZnO affected the formation of cristaobalite by consuming of Li+ ion and the

increase of SiO2-rich phase fraction which is crystallized. Also, it impeded

growth of LS2 crystalline phase.

The bi-axial strength and hardness increased as decrease of crystalline phase size.

I-1. Crytallization of Lithium Disilicate Glass-Ceramics by Mixture Design


16/40

I-2. Effect of crystallization on mechanical

properties of lithium disilicate glass ceramics


17/40

17

Part I-2. Motivation & Objective

2/1 dkyyf

Y : Crack shape factor

• σf is the yield stress for the easiest slip system of a single crystal

• ky is constant

2/1 cYKI

2/12/1 dY

Kc

Y

K ICICf

2/1

0

dkHH h

Fine-grained branch

<25㎛

<Al2O3-polycrystalline>

Ref) http://www.georgevandervoort.com/metallography/specific/iron-and-steel-

specific/20001306-revealing-prior-austenite-grain-boundaries-in-heat-treated-steels-

article.html

<9310 alloy steel> <4340 alloy steel>

Dislocation Pile-up

Ref) http://www.ceramtec.kr/ceramic-

materials/aluminum-oxide/

<Al2O3> <Li2Si2O5>

<Metal> <Ceramics> <Glass Ceramics>

1. Does the strength and hardness of crystalline phase of LS2 glass-ceramics

follows the Hall-Petch relation?

2. What factors would influence on the strength & hardness of LS2 glass-

ceramics?

<Hall-Petch relation>

<Griffiths eq.>

Hall-Petch relation + Griffiths eq.

Ref) Mechanical properties of ceramics

(John. B. Wachtman) p215

Ref) Wikipedia : Hall—Petch Strengthening

sizeGrain Crack

Assumption)

Grain size, d-1/2

d~10n

m

σ


18/40

18

Additives P2O5 ZnO K2O

Raw materials (NH4)2HPO4 ZnO K2CO3

Role Nucleation agent Glass modifier

•SiO2/Li2O=2.3 (94mol% fixed)

• Additives total : 6mol%

<Glass composition>

Heat-treatment affects the number of nuclei, size of

crystalline phase

Nucleation temperature, time → The number of nuclei

- Crystal growth temperature, time→ Crystalline phase size

<Crystallization>

Sample

IDComposition SiO2 Li2O P2O5 ZnO K2O

#3 P1.5Zn3 66.27 27.73 1.5 3 1.5

#4 P1.25Zn2.75 66.27 27.73 1.25 2.75 2

#7 P1.25Zn2 66.27 27.73 1.25 2 2.75

#12 P1Zn2.5 66.27 27.73 1 2.5 2.5

Heating

Tg : 440oC

Tm : 990oC

Ref) http://polymer-additives.specialchem.com/centers/polypropylene-nucleation-

center/how-do-nucleating-agents-work

Experimental


19/40

19

<Crystal growth : Heat-treatment condition>

Max. Nucleation Temp. →

Nucleation Temp. Crystal growth Temp. Crystal growth Time

460

8002

4

8502

4

500

8002

4

8502

4

540

8002

4

8502

4

<Strength : Bi-axial >

<Hardness : Vicker’s >

• ISO 6872

• Piston on a 3-balls

• Sample size : 12.8mm(Dia), 1.2T

<Fracture Toughness : SEVNB>

• Single-Edge-V-Notch-Beam

• Notch depth : 1mm, Tip Radius: 15μm

• Sample size : 3 × 4 × 40 (mm)

<3-point>

NotchSpan : 30mm

• Indentation load: HV 0.5

• Duration time : 10s

Isothermal : 1h

Heating rate : 15℃

<Maximum nucleation Temperature>→ Marrota’s DTA analysis

0

0

0

00

0

0

11)ln(

)0( sample quenched-asan for 1

ln

rate heating & surface same

nucleated previouslyfor 1

)ln(

pp

cn

n

p

c

p

cn

TTR

E

N

NN

NconstTR

EN

N

constTR

ENN

raturepeak tempeDTA theofshift pp TTT

→ Max. nucleation rate

Ref) A. Marrota et al, J. Mat. Sci. 16 (1981) 341

• Nucleation duration: : 1h (fixed)

• Heating rate : 10℃/min

• Crystal growth

• Heating rate : : 30℃ /min

Experimental

0

200

400

600

800

1000

1200

1400

1600

NucleationAnnealing

Forming

Crystallizaion

Tem

pe

ratu

re (

oC

)

Time (min)

Melting

Glass fabrication :

Melt-Quenching method

<Experimental>


20/40

20/14

Crystal growth

Temp.800oC 850oC

Crystal growth

Time2h 4h 2h 4h

0

460oC

500oC

Max.Nucleation

Temp.

Nu

clea

tion

Tem

p.

10㎛ 10㎛10㎛ 10㎛

10㎛ 10㎛10㎛ 10㎛

10㎛ 10㎛10㎛ 10㎛

length

width

20/14

5004600

850800850800850800

424242424242

14

12

10

8

6

4

2

Length

(㎛

)

Nucleation Temp.

Crystal growth Temp.

Crystal growth Time

5004600

850800850800850800

424242424242

5

4

3

2

1

0

Wid

th (㎛

)

Crystalline phase size : P1Zn2.5


21/40

21/14

Crystal growth

Temp.800oC 850oC

Crystal growth

Time2h 4h 2h 4h

460oC

500oC

Max.Nucleation

Temp.

540oC

Nu

clea

tion

Tem

p.

5㎛ 5㎛ 5㎛

5㎛

5㎛ 5㎛ 5㎛ 5㎛

5㎛ 5㎛ 5㎛

5㎛

540500460

850800850800850800

424242424242

7

6

5

4

3

2

1

Asp

ect

ratio

Nucleation Temp.


Crystal growth Time

540500460

850800850800850800

424242424242

1.4

1.2

1.0

0.8

0.6

0.4

0.2

0.0

Wid

th (㎛

)

540500460

850800850800850800

424242424242

4

3

2

1

0

Length

(㎛

)

length

width

Crystalline phase size : P1.25Zn2


22/40

22/14

Crystal growth

Temp.800oC 850oC

Crystal growth

Time2h 4h 2h 4h

460oC

500oC

Max.Nucleation

Temp.

540oC

Nu

clea

tio

n T

emp

.

5㎛ 5㎛ 5㎛

5㎛

5㎛ 5㎛ 5㎛ 5㎛

5㎛ 5㎛ 5㎛

5㎛

540500460

850800850800850800

424242424242

6

5

4

3

2

1

Asp

ect

ratio

540500460

850800850800850800

424242424242

2.5

2.0

1.5

1.0

0.5

Length

(㎛

)

Nucleation Temp.


Crystal growth Time

540500460

850800850800850800

424242424242

1.0

0.8

0.6

0.4

0.2

Wid

th (㎛

)

length

width

Crystalline phase size : P1.25Zn2.75


23/40

Crystal growth

Temp.800oC 850oC

Crystal growth

Time2h 4h 2h 4h

460oC

500oC

Max.Nucleation

Temp.

540oC

23/14

Nu

clea

tion

Tem

p.

1㎛

1㎛

1㎛

1㎛

1㎛

1㎛

1㎛

1㎛

1㎛

1㎛

1㎛

1㎛

Nucleation Temp.


Crystal growth Time

540520460

850800850800850800

424242424242

1.4

1.2

1.0

0.8

0.6

0.4

0.2

0.0

Wid

th (㎛

)

540520460

850800850800850800

424242424242

3.0

2.5

2.0

1.5

1.0

0.5

0.0

Length

(㎛

)

length

width

540520460

850800850800850800

424242424242

6

5

4

3

2

1

Asp

ect

ratio

P1Zn2.5 P1.5Zn3P1.25Zn2.75

2㎛ 2㎛

P1.25Zn2

2㎛2㎛

Heat treat-ment : 500oC, 800oC, 2h

Crystalline phase size : P1.5Zn3


24/40

24/14

Lithium Disilicate [01-072-0102]

Cristobalite – SiO2 [01-071-0785]

• From the Li2O-rich region, Li3PO4 was formed and it

promoted the LS2 growth.

• SiO2-rich region may be left as increase of P2O5 and it

formed cristobalite (SiO2).

• ZnO may consumed the Li+ to maintain neutrality in

the glass which result in increase of SiO2-rich region

leading the cristobalite (SiO2) growth.

10 20 30 40 50

P1.5Zn3

P1.25Zn2.75

P1.25Zn2

Inte

nsity (

a.u

.)

2-theta (deg.)

P1Zn2.5

(101)(020)

(110)SiO2/Li2O=2.39

Composition SiO2 Li2O P2O5 ZnO K2O

P1.5Zn3 66.27 27.73 1.5 3 1.5

P1.25Zn2.75 66.27 27.73 1.25 2.75 2

P1.25Zn2 66.27 27.73 1.25 2 2.75

P1Zn2.5 66.27 27.73 1 2.5 2.5

• Secondary phase cristobalite peak increased as increase of P2O5 and ZnO.

• P2O5 induced phase separation the Li2O-rich region and SiO2-rich region.

<Phase separation>

Ref) Glass-ceramics technology (Wolfram Hölnad) p50

Crystalline phase analysis : XRD


25/40

25/14

1129

2.8

2.6

2.4

2.2

2.0

1.8

Fra

ctu

re t

oughness (

MP

a m

-1/2)

<Fracture toughness. KIC>

→ All KIC of samples was identical

→ No siginificance

Comparison p-value

P1Zn2.5 vs P1.5Zn3 0.758

P1Zn2.5 vs P1.25Zn2 0.066

P1.25Zn2 vs P1.5Zn3 0.109

2/12/1 dY

Kc

Y

K ICICf

4㎛

12.1Y

Composition KIC

Crystalline phase size (㎛)

P1.5Zn3 2.29±0.34 0.361

P1.25Zn2.75 - 0.962

P1.25Zn2 2.07±0.3 1.026

P1Zn2.5 2.34±0.11 3.878

12.1

ICKslope

Composition KIC Slope

P1.5Zn3 2.29±0.34 1.15

P1.25Zn2 2.07±0.3 1.04

P1Zn2.5 2.34±0.11 1.18

Hall-Petch relation + Griffiths eq.

P1Zn2.5 P1.25Zn2 P1.5Zn3

sizeGrain Crack

Assumption)

Fracture toughness


26/40

26/14

0 500 1000 1500 2000 2500150

200

250

300

350

400

450

500-- 4.00 1.00 0.44 0.25 0.16

P1.5Zn3

P1.25Zn2.75

P1.25Zn2

P1Zn2.5

(Crystalline phase width)-1/2

,d-1/2

(m-1/2

)

Crystalline phase width, d (μm)

Fra

ctu

re s

tre

ng

th,

f (M

Pa) <Width>

• The calculated slope from the crystalline phase size signified

the relevance with KIC showed very low value compared to

the measurement → (P1Zn2.5 : 0.382 vs 1.18)

• This is explained that the crystalline phase size is too

small(<4㎛), hence the only Hall-Petch corresponded.

• Fracture strength increased as decrease of crystalline

phase size (length, width) until critical point and it showed

the deviation and decrease. It could be attributed to the

presence of secondary phase cristobalite (SiO2).

2/1 dkyyf

Slope : 0.112

12.1

ICKslope

Composition KIC

Slope (Calculated)

Slope (Measured)

P1Zn2.5 2.34±0.11 1.18 0.382

2/12/1 dY

Kc

Y

K ICICf

Hall-Petch relation + Griffiths eq. <Length>

0 500 1000 1500 2000150

200

250

300

350

400

450

500-- 4.00 1.00 0.44 0.25

P1.5Zn3

P1.25Zn2.75

P1.25Zn2

P1Zn2.5

Crystalline phase length, d (μm)

Fra

ctu

re s

tre

ng

th,

f (M

Pa

)

(Crystalline phase length)-1/2

,d-1/2

(m-1/2

)

length

width

Slope : 0.382

sizeGrain Crack

Assumption)

Srength vs Crystalline phase size


27/40

0 500 1000 1500 2000 25004

5

6

7-- 4.00 1.00 0.44 0.25 0.16

(Crystalline phase width)-1/2

,d-1/2

(m-1/2

)

Vic

ker's h

ard

ne

ss (

GP

a)

Crystalline phase width, d (μm)

P1.5Zn3

P1.25Zn2.75

P1.25Zn2

P1Zn2.5

27/14

2/1

0

dkHH h

• Vickers hardness increased as decrease of crystalline phase

size (length, width).

• Even though fracture strength did not followed the Hall-

Petch relation, the hardness coincided with it.

0 500 1000 1500 2000 25004

5

6

7-- 4.00 1.00 0.44 0.25 0.16

P1.5Zn3

P1.25Zn2.75

P1.25Zn2

P1Zn2.5

Crystalline phase legnth, d (μm)

Vic

ker's h

ard

ne

ss (

GP

a)

(Crystalline phase length)-1/2

,d-1/2

(m-1/2

)

7741.0:

84.4:

4-9.27E:

2

0

R

H

kh

length

width

5402.0:

78.4:

4-6.03E:

2

0

R

H

kh

Hardness vs Crystalline phase size


28/40

28/14

- Composition)

1) The nucleation agent P2O5 promoted nucleation, therefore, crystalline phase became small.

2) As increase of P2O5 and ZnO, secondary phase cristobalite peak intensity increased.

Why? : The Li+ ion was consumed to form Li3PO4 crystal which promoted the LS2 growth, and to

maintain the neutrality in Zn2+ tetrahedron.

- Crystallization) The crystalline phase grew as increase of crystal growth temperature and time.

Does the strength and hardness of crystalline phase of Lithium disilicate glass-ceramics

follows the Hall-Petch relation?

- Fracture strength : No. It showed scattering and decrease and deviation at critical point.

Why? : It is assumed that the secondary phase cristobalite(SiO2) could affected fracture strength.

- Hardness : Yes. It followed the Hall-Petch relation.

Why? : It will be studied further in future work.

Effect of crystallization on mechanical properties of lithium disilicate glass-ceramics

Surmmary


29/40

II. Effect of the colorants on the color and

translucency of lithium disilicate glass-

ceramics


30/40

• Lambert’s law : 흡광도는 cell의 길이에 비례 A=ab, a=constant, “absorptivity” [L/g cm or L/mole cm]

• Beer’s law : 흡광도는 시료의 농도에 비례 A=a`c, c=concentration [g/L, mole/L]

• Lambert-Beer’s law = A=abc

Optical density (Absorbance)

0

0

log=log=

100×=%

P

PTAbsorbance

P

PT

-

Principles of colour


31/40

Absorption by

transition metal

d block

3d orbitals filling

3d, 4f metal ion이 light을 선택적으로 흡수(보색이 반사되어 색으로 나타남)

Metal 이기 때문에 emission이 아님.

Metal 이온이 LS2 crystalline phase 혹은 이차상(Cristobalite, quartz, LS, LP), 유리상에 위치(확실한 위치는 알 수 없음 분석필요)Fig. 6. Band diagram of a typical metal (A)

showing light absorption transitions in

Absorption of light


32/40Crystal Field Theory


33/40

33/22Ref) https://scilearn.sydney.edu.au/fychemistry/calculators/colour_wheel.shtml

Complimentary colour


34/40

34/22

<Redox in soda lime glass>

+4+3+3+4 Sb+CeSb+Ce →Yellow Weak yellow

Ce4+ Ce3+

Cr2O3-Mn2O3-CeO2-V2O5-CuO-As2O3-Sb2O3-Fe2O3

Ref) Chemical approach to Glass, Milos Bohuslav Volf

High oxidation potential

<Redox potential series in soda lime glass>

Factors of color generation in glass

• Type and concentration of polyvalent ions

• Redox state of glass

• Oxygen pressure and so on http://artglassdesigns.blogspot.kr/2014/12/colored-glass.html

<Colors generated by colorants in soda lime glass>

Ref) Fundamentals of Inorganic Glasses, Arun K. Varshneya

Color generation in glass


35/40

Ref) http://www.konicaminolta.com/instruments/knowledge/color/part3/02.html

Usually, a person looks at the color of the object and ignores the

specular reflection of the light source. SCE mode would be

sufficient to express colour

Brightness, lightness, luminance, or value, which describes the intensity of the colour, the

number of photons reaching the eye.

SCE (Specular Component Excluded)

SCI (Specular Component Included)

L* (Lightness )


36/40

Reference

Sample

Mask

Mask

• Shimadzu UV-2600

• Integrating sphere for diffuse reflectance

• 240~1400nm

DR

SR

When the specular reflectance is measured,

the samples locates in SR position which is

tilted 8 degree.

Uv-vis spectrometer


37/40

400 500 600 7000

20

40

60

80

100

Diffu

sed r

eflecta

nce (

%)

Wavelength (nm)

V2O5 0

V2O5 0.05

V2O5 0.1

V2O5 0.25

V2O5 0.5

400 500 600 7000

20

40

60

80

100

Diffu

sed r

eflecta

nce (

%)

Wavelength (nm)

MnO2 0

MnO2 0.05

MnO2 0.1

MnO2 0.25

MnO2 0.5

V2O5 (mol%)

L* a* b*

0 69.7 -1.3 -2.4

0.05 67.5 -3.7 3.3

0.1 63.5 -4.7 6.9

0.25 53.3 -5.1 17

0.5 42.5 0.4 21.9

MnO2 (mol%)

L* a* b*

0 69.7 -1.3 -2.4

0.05 71.8 -0.9 -2.8

0.1 70.5 -0.6 -2.4

0.25 69.2 0.2 1.8

0.5 64.1 1.6 -0.7

400 500 600 7000

20

40

60

80

100

Diffu

sed r

eflecta

nce (

%)

Wavelength (nm)

MnO2 0

MnO2 0.05

MnO2 0.1

MnO2 0.25

MnO2 0.5

MnO2 1

MnO2 (mol%)

L* a* b*

0 67.5 -3.7 3.3

0.05 66.7 -3.4 3.6

0.1 63.5 -3.1 3.9

0.25 63.5 -2.1 6.3

0.5 57.5 -0.6 9.2

1 47.3 0.2 16.9

-6 -4 -2 0 2 4 6-5

0

5

10

15

20

25

0.5

0.25

0.1

0.05

0

1

0.5

0.25

0.10.05

1

0.5

0.25

0.1

V2O5 0~0.5 mol%

MnO2 0~1 mol%

V2O5 0.05 + MnO2 0~1 mol%

b*

a*

0.05

0.0 0.2 0.4 0.6 0.8 1.040

60

80

100

V2O5

MnO2

V2O5 0.05 + MnO2

Lig

htn

ess (

L*)

Amount of additives (mol%)

+V2O5 0.05mol%

4

3

2

1

0

A4

A3

A2

A3.5

A1

A4

A3.5

A3

A1

A2

HT

LT

MO

Diffused reflectance, L*a*b*


38/40

300 400 500 600 700 8000

20

40

60

80

100

Tra

nsm

itta

nce (

%)

Wavelength (nm)

V2O5 0

V2O5 0.05

V2O5 0.1

V2O5 0.25

V2O5 0.5

300 400 500 600 700 8000

20

40

60

80

100

Tra

nsm

itta

nce

(%

)

Wavelength (nm)

MnO2 0

MnO2 0.05

MnO2 0.1

MnO2 0.25

MnO2 0.5

300 400 500 600 700 8000

20

40

60

80

100

Tra

nsm

itta

nce

(%

)

Wavelength (nm)

MnO2 0

MnO2 0.05

MnO2 0.1

MnO2 0.25

MnO2 0.5

300 400 500 600 700 8000

1

2

3

4

5

Ab

s.

Wavelength (nm)

V2O

5 (mol%)

0

0.05

0.1

0.25

0.5

300 400 500 600 700 8000

1

2

3

4

5

Ab

s.

Wavelength (nm)

MnO2 (mol%)

0

0.05

0.1

0.25

0.5

300 400 500 600 700 8000

1

2

3

4

5

Abs.

Wavelength (nm)

MnO2 (mol%)

0

0.05

0.1

0.25

0.5

T%, Abs.

+V2O5 0.05mol%

V5+V3+


39/40

39/22

UV–Vismeasurementswere obtained in the

transmission mode in the

range from 200–1200 nm. The spectra were

converted into absorbance

and normalized to the sample thickness (optical

density in cm−1).

Literature survey


41/33

500 600 700 800 900

678.3

663.3

642.5

Temperature (oC)

15K/min

20K/min

10K/min

5K/min

Endo

Exo

615.3

41500 600 700 800 900 1000

740.4

812.5

788.2

20K/min

15K/min

10K/min

5K/min

Temperature (oC)

Endo

Exo

740.4

500 600 700 800 900 1000

732.2

809.6

782.6

Temperature (oC)

20K/min

15K/min

10K/min

5K/min

Endo

Exo

732.2

500 600 700 800 900

676.6

662.2

643.3

Temperature (oC)

En

do

Exo

15K/min

10K/min

5K/min

20K/min

615.4

500 600 700 800 900

577

613.9

591.9

Temperature (oC)

5K/min

10K/min

15K/min

20K/min

E

nd

oE

xo

577

#1

#7 #8

#12 #13

500 600 700 800 900

694

677

656

Temperature (oC)

15K/min

20K/min

10K/min

5K/min

En

do

Exo

625.8

500 600 700 800 900

697.7

721.9

712.4

727.2

632.3

620.9

605.7

Temperature (oC)

5K/min

10K/min

15K/min

20K/min

E

nd

oE

xo

583.7

500 600 700 800 900

742.8

734.3

725.7

716.9

617

613.9

577.1

591.8

Temperature (oC)

20K/min

15K/min

10K/min

5K/min

En

do

Exo

500 600 700 800 900

Temperature (oC)

775.2

765.4

752

730.7693

707

718

727

640.6

627.9

61515K/min

20K/min

10K/min

5K/min

En

do

Exo

589.5

Discussion : Differential Scanning Calorimeter

#2 #3

#6

FE-SEM EDS Mapping

ElementWeight%

Atomic%

실투입(mol%)

O K 17.13 68.98

Si K 11.38 26.10

P K 0.53 1.09

K K 1.28 2.11

Ti K 0.15 0.20

V K 0.34 0.43

Zn L 0.88 0.86

Ce L 0.52 0.24

Totals 32.18

분석처 : KICET JEOL 6701F

Sample : 1) CeO2 0.5 TiO2 0.5 V2O5 0.5 (HF Etching X)

EDS resolution 작음 point로 찍으면 다른 부분까지 나옴

TEM (FIB) : Base(#12), CeO2 0.5 V2O5 0.5

43/22

분석처 : 가천대 Tecnai G2 F30 (300kV)

FIB : 가천대 나노기술혁신센터 FIB-STEM FEI Nova 200

Base : #12 기본 조성 (no colorant)

Hydro carbon damages

Ga 오염? 까만점들 (out focusing)

Cleaning 문제?

결정 터짐 carbon coaring 필요(터지는 시간 줄임) 회색빛 정도

FE-SEM EDS Mapping

• 5kV에서 Aperture Size 가 120 μm 경우 damage 발생 EDS Mapping 중 damage 발생 가능• KICET JEOL 6701F 에서는 15kV 15 current 맞춰도 damage 발생 X

Fundamentals of inorganic glasses, A. K. Varshneya , Physical ceramics, Yet-Ming Chaing, Dunbar Birnie III, W. David Kingery, (p437-)

m

x

x

x

TRT

TH

aN

fRTU

RT

G

a

DU

RT

EaD

RT

G

RT

EaUvva

RT

GEv

RT

Ev

f

2

0

2

0

0

exp13

exp1

exp

exp1exp)21(

)(exp2

exp1

Wilson-Frenkel theory

aN

RTD

3

Stokes-Einstein relation between the

diffusion coefficient and the viscosity

Crystal growth rate

According to Turnbull(1960) : reaction-rate theory, • υ frequency with which atoms are transported across the interface

• a0 : distance the crystal advances for a layer of attached molecules

• ΔGx : free energy of crystallization

0

f0

aU

TRT

THaU

m

ΔGm<<RT, Small undercooling

ΔGm>>RT Large undercooling

Crystal growth velocity is ~ 105cm/sec

과냉각이 작을 때 성장율은 ΔH, ΔT에 비례!

과냉각이 클 때는 한계값 도달! (점도가 높아짐)

ΔE’

ΔGx

ΔE’+ΔGx

Glass-Ceramics, P. W. Mcmillan 2nd edition

1) The irregular glass structure can be re-arranged into the

periodic lattice of the growing crystal

2) Energy released in the phase transformation process can

be eliminated by the heat flow away from the crystal-glass

interface

RT

G

RT

EaU xexp1exp0

a0 : interatomic seperation

υ : vibrational frequency at the crystal-glass interface

Bulk free energy of

crystallization

Energy barrier i.e.

activation energy

2

0

2

0

3

exp

aN

RTD

kT

EaD

0

2

0

2

0

3exp1

exp13

Na

fR

kT

GT

UU

RT

G

aN

fRTU

x

R

x

RT

EUU

RT

E

a

fDU

RT

EDD

kT

G

a

fDU

u

xu

exp

exp

exp

exp1

0

0

0

0

0

Negligibly small

compared with Du

Matusita

J. Mat. Sci, 10

(1975) 961

Vogel

Crystal growth rate

Reduced growth rate UR

Lithium Disilicate Glass-ceramics for dental applicationsocw.snu.ac.kr/sites/default/files/NOTE/01a....

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