o54-surface tension and density of liquid ag-cu alloys

Surface tension and density of liquid Ag -Cu alloys

Foundry

Research

Institute

of liquid Ag -Cu alloys

Przemyslaw Fima1,2 and Natalia Sobczak1

1 - Center for High Temperature Studies, Foundry Research Institute, Krakow

2 - Institute of Metallurgy and Materials Science PAS, Krakow

E-mail: [email protected]

• Introduction

• Results for pure Ag

• Results for Ag-Cu alloys

– Density and molar volume

Presentation plan

– Surface tension

– Modelling of the surface tension

• Summary

TOFA 2010, Discussion meeting on thermodynamics of alloys, 12-16.09.2010, Porto

Ag-Cu system:

• A subsystem of ternary andmulticomponent solders

– Ag-Cu-Sn – Ag-Cu-Sn-In

Introduction

• A braze alloy for joining of metals and ceramics

– Ag-Cu– Ag-Cu-Ti


www.nims.go.jp/cmsc/pst/database/agelem/agcu/

• Investigated by a few groups:– relatively good agreement of density data– some differences in surface tension data

Introduction

Author (Year) DensitySurface tension

Krause et al. (1929) + +


Krause et al. (1929) + +

Bricard et al. (1973) +

Sebo et al. (1977) + +

Lee et al. (2004) +

Novakovic et al. (2005) +

Kucharski et al. (2006) + +

Brillo et al. (2006) +

Experimental procedure

• Materials: Ag (5N), X(Cu): 0.3; 0.4; 0.5

• Sessile drop method

• Ar (6N) protective gas

• 1098 – 1573 K, temperature • 1098 – 1573 K, temperature decreasing stepwise

• Hold time 10 min

• Surface tension calculated with AstraView®, developed by CNR-IENI, Genoa, Italy N. Sobczak et al. Mater Sci Eng A495 (2008) 43


Surface tension measurement

-0.5

-0.45

-0.4

-0.35

-0.3

-0.25

-0.2

-0.15

-0.1

-0.05

0-0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4

1. capture the image2. change the image into

a set of coordinates3. fit the solution of Laplace

equation to coordinates


Rotenberg et al., J Colloid Interf Sci 93 (1983) 16 9

Ag (pure) - density

ρL (g· cm-3)

ρT (g·cm-3 K-1)

Method Atmosphere Temperature

(K) Year

9.237 -0.00065 A – 1273 – 1473 1929 9.28 -0.0009 A – 1234 – 1573 1951 9.302 -0.000959 A N2 1234 – 1573 1953 9.348 -0.0011 MBP H2 1323 – 1423 1960 9.346 -0.0009067 A – 1234 – 2450 1962 9.337 -0.00105 MBP Ar 1234 – 1673 1964 9.36 -0.00108 MBP Ar 1273 – 1473 1969 9.36 -0.00108 MBP Ar 1273 – 1473 1969 9.301 -0.00105 SD Ar 1253 – 1381 1971 9.32 -0.00097 A N2 + 10% H2 1234 – 1773 1972 9.321 -0.0009787 A – 1234 – 1400 1975 9.31 -0.00078 SD Ar, H2 1234 – 1873 1989 9.346 -0.000911 MBP Ar + 10% H2 1273 – 1473 2003 9.304 -0.00071 SD Ar 1273 – 1523 2005 9.15 -0.00074 EML He + 8% H2 1250 – 1380 2006 9.288 -0.001175 SD Ar 1273 – 1573 2010

A – Archimedean principle, EML – electromagnetic levi tation, MBP – maximum bubble pressure, SD – sessile drop meth od


Ag (pure) - density

9,1

9,2

9,3

9,4

Den

sity

, g c

m-3


8,8

8,9

9,0

9,1

1200 1250 1300 1350 1400 1450 1500 1550 1600

Den

sity

, g c

m

Temperature, K

Brillo et al. (EML)

Gasior et al. (MBP)

Kucharski et al. (SD)

This work (SD)

Ag (pure) – surface tensionρL

(mN· m-1) σT

(mN·m-1 K-1) Method Atmosphere

Temperature (K)

Year

946.0 -0.4 SD Vac. 1248 - 1298 1953 884.9 -0.17 MBP - 1273 - 1473 1958 898.4 -0.135 MBP - 1273 - 1473 1958 900.4 -0.1883 MBP H2 1273 - 1523 1960 913.0 -0.155 MBP H2 1273 - 1473 1964 921.3 -0.174 MBP - 1800 - 2330 1968 957.5 -0.14 SD Vac. 1246 - 1346 1970 910.7 -0.117 SD Ar 1253 - 1381 1971 910.7 -0.117 SD Ar 1253 - 1381 1971 926.0 -0.15 SD He 1234 - 1573 1972 890.0 -0.16 SD He 1253 - 1373 1982 910.0 -0.17 SD Ar, H2 1270 - 1860 1986 924.0 -0.19 EML Ar, H2 1273 - 1383 1986 898.3 -0.1905 MBP Ar + 10% H2 1273 - 1473 2003 925.6 -0.228 SD Ar + 10% H2 1269 - 1473 2004 914.0 -0.15020 SD Ar 1234 - 1473 2005 912.3 -0.204 SD Ar 1273 – 1523 2005 984 -0.298 EML Ar + 5% H2 1234 – 1734 2008

919.8 -0.176 SD Ar 1273 – 1573 2010


Ag (pure) – surface tension

890

900

910

920

930

Sur

face

tens

ion,

mN

m-1

840

850

860

870

880

1200 1250 1300 1350 1400 1450 1500 1550 1600

Temperature, K

Sur

face

tens

ion,

mN

m

Mills and Su (review)

This work (SD)


Ag-Cu alloys - density

8.8

8.9

9

9.1

9.2

9.3

Den

sity

, g c

m-3

8.2

8.3

8.4

8.5

8.6

8.7

1000 1100 1200 1300 1400 1500 1600

Temperature, K

Den

sity

, g c

m

Ag (pure)X(Cu) = 0.3X(Cu) = 0.4X(Cu) = 0.5


Ag-Cu alloys – molar volume

10

10.5

11

11.5

12

Mol

ar v

olum

e, c

m3

mol

-1

7.5

8

8.5

9

9.5

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

X(Cu)

Mol

ar v

olum

e, c

m

Krause and Sauerwald (A)Sebo et al. (SD)Brillo et al. (EML)Kucharski et al. (SD)This work (SD)

1373 K


Ag-Cu alloys – surface tension

920

940

960

980

1000

Sur

face

tens

ion,

mN

m-1

840

860

880

900

920

1000 1100 1200 1300 1400 1500 1600

Tempeature, K

Sur

face

tens

ion,

mN

m

Ag (pure)X(Cu) = 0.3X(Cu) = 0.4X(Cu) = 0.5


• The Butler equation

• The partial Gibbs free energy of the component i

Modelling of the surface tension

( )Exi

sExi

ii

si

ii GG

Ax

x

A

RT −−+= )()( 1

lnσσ

• The partial Gibbs free energy of the component i

• Parameters L from COST 531 thermodynamic database

( ) ( ) ( ) ( ) ( ) ( )( )[ ]...53 2102 +−−+−+= −−− ijijjiijjijijExi xxxxLxxLLxG

Exi

sExi GG ⋅= β)(



1200

1300

1400

1500

Sur

face

tens

ion,

mN

m-1

Sebo et al. (SD)Kucharski et al. (SD)Krause et al. (MBP)Bricard et al. (SD)Lee et al. (SD)Novakovic et al. (SD)

1373 K

800

900

1000

1100

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1X(Cu)

Sur

face

tens

ion,

mN

m

This work (SD)



0.5

0.6

0.7

0.8

0.9

1

X(A

g) in

the

surf

ace

laye

r

0

0.1

0.2

0.3

0.4

0.5

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

X(Ag) in the bulk

X(A

g) in

the

surf

ace

laye

r

1373 K1573 K


• Our data for pure Ag agree well with literature dat a

• Density of Ag-Cu alloys decreases with increasing t emperature and with increasing concentration of Cu

• Molar volume shows additive behavior in the whole r ange of Ag-Cu compositions

• Surface tension decreases with temperature and incr eases with Cu content, a small change of slope is observed

Summary

content, a small change of slope is observed

• There is a good agreement of experimental data with surface tension calculated with the Butler equation

• Surface layer of Ag-Cu solution is enriched with si lver


P. Fima, N. Sobczak (2010) Int J Thermophys, doi: 10.1007/s10765-010-0798-5

This work was financially supported by the Ministry of Science and Higher Education of Poland under the project no .

PBZ/MNiSW/07/2006/56, in the years 2007 – 2010

Thank you for your attention!


Ag-Cu alloys – surface tension

-0.1

-0.05

0

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

X(Cu)

-0.3

-0.25

-0.2

-0.15

dσσ σσ/

dT

This workKucharski et al.Novakovic et al.



1100

1200

1300

1400

Sur

face

tens

ion,

mN

m-1 beta = 1

beta = 0

1373 K

800

900

1000

1100

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1X(Cu)

Sur

face

tens

ion,

mN

m


• …

….


( ) Czhgrr

+−=

+ ρσ

21

11

o54-surface tension and density of liquid ag-cu alloys

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