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Thermodynamic properties of liquid CuSnZn alloys
Journal of Alloys and Com~xmds 247
: lW7 I IXS-IX9
Thermodynamic properties of liquid Cu-Sn-Zn
alloys
Ming Peng, Adolf Mikula*
Abstract Using an appropriategalvanic cell. the partial free energies of lint in liquid Cu-Sn-Zn alloys were deremuned ins a function of propcnies were obtained liar 40 alloys. Their composition was situated WI four and temperttture. Thermodynamic cross-sectionswith constantratios Cu:Sn of I :3. I:?. I :I and 2: I. Th’ L mtegralfree energy and the intcgnl cnthalpyfor the remary system ill 1023 K were calculated by Gihhs-Duhem integration. concentration
1. Introduction
polished with a tine emery paper and zinc was cleaned
Owing to health concerns and environmental reasons. lead will be replaced in the near future in all solder materials. New lead-free solders must be developed. and for certain applications the ternary X-Sn-Zn alloys could be candidates. We have already investigated the Ag-SnZn [II and Au-Sn-Zn 121 systems. Since copper alloys have excellent electrical properties and high corrosion
prior to its use by melting under vacuum and filtering through quartz wool under a purified argon atmosphere. Copper was used without further puritication. The metals were weighed and sealed in silica capsules under vacuum and melted together at 1300 K tar several days. After heat treatment the alloys were quenched in ice 3 g of each alloy composition water and approximately was used for the e.m.f. measurements.
resistance, they are important materials for different industrial applications. However. data of thermodynamic properties and of the phase diagram are scarce for ternary copper alloys. Thermodynamic data are also needed for the calculation of phase diagrams and for the improvement of industrial processes. In the present investigation the thermodynamic properties of zinc were measured with an e.m.f. method at four cross-sections with a constant Cu:Sn molar ratio of 21. I: I. I:2 and l:3. A Gibbs-Duhem integration was applied to determine the integral thermodynamic properties for the whole ternary system. From the discontinuities in the slope of the e.m.f. versus temperature curves the liquidus temperature for most alloys was determined.
As electrolyte. the euteetic mixture KCI-LiCI with addition of 0.5 ntoF& ZnClz was used. The preparation of the electrolyte and the assembly of the e.m.f. cell are described by Geffken et al. 131. Measurements were carried out on heating and cooling. The heating and cooling rate was 8 to 10 K h-l. Every 50 degrees the temperature was kept constant for a longer period of time to check the stability of the e.m.f. The temperature range of measurements was from the liquidus up to II00 K. The following atrangement for the experiment was used: Zn(l)/Zn
_’(KCI-LiCI)(I)/Cu-Sn-Zn
alloy(l)
Under reversible conditions, the Gibbs free energy change for the reaction is given by
2. Experimental procedure
AC,,
The ternary alloys were prepared from high purity metals (4 N copper from Fischer Scientific Co., NJ; 5 N tin
where F is the Faraday constant (96 486 C mol-‘), E the electromotive force of the cell, R theuniversal gas constant (8.31434J mole’ K-l). T the absolute temperature and a,, the thermodynamic activity of zinc in the ternary alloy, with pure liquid zinc constituent as reference state. At all four cross-sections the e.m.f. versus temperature curves
and zinc from Johnson Matthey GmbH, Vienna,). In order to remove the oxide layer from the surface, Sn was ‘Conespading
author.
0925~8388/97/$17.00 0 1997 Elwier PI/ SO925-8388(96)02575-3
Science S.A. All rights reserved
= - 2FE = RT In (I~”
(1)
This system was evaluated by Hultgren et al. E(mV
) = ,I + h/i K)
(1)
For cxh expsrimrnr two cooling curves were recordrd. The ;pwment hrtwern these two curves was wry good. The drvkuion of the measured r.m.f. values from the tittrd one> \\;a\ ::.0.7 mV ;u 5 and IO at.% Zn. between 50. I and 20. IS IT’S.at ali other compositions. Using the measured values of E. Ihe (I,,, and AC?,,, at a temprramre were calculated. From the temperature drpcndence of E. the partial molar entropy As,,, and were derived. using the following equarnthalpy Xi,,, tions: given
as,,, = ‘FIXlilT)\,,.
= 2hF
(3)
thermodynamic Spencer I I7 I.
re-evaluation
Some information
is given
on this ternary
- El = G,,,
+ 7Is,,,
= - 2oF
The man
(4)
kihhs-Duhem 141 (eq.
(12)
equnrion
given
their
publication)
in
by Elliott
system is given by
l’ahle I Measured e.w.f. datn a,.‘% %n
E m.T.
was
the integral thermodynamic quantities whole ternary system from the e.m.f. data.
- I4.wJ0 + 0. I xixwi K, - 12.MN,+O.l INiT - ,2,1X0+0,077’,27(K, ~~IO.IXOIO.OMW17iK)
7xs xos X6.3 WJ.3 P I ‘J
-Y.?73+0.0,47lXT(K~ --X.-EL) +O.O35477I K,
10
SY.YY
- Y.07’) + U,U?X’JYT( K ,
XX.3
for the
70.00
mX.2X.l t0.023127’~K1
xx0
79.Y’J
-4.Sh.l f 0.013YOTl
~JU.01
-Oh’)3 + U.UUSYhT~ K)
applied
determine
S.“l lO.Ul I’,.‘,‘~ 3U.Ul 3Y,OCJ -l’J.Y’J
and Chip-
KI
Yl7
X43 __
/hJ (‘rr:91 I:2 ~.n~.~.~-s~,~.rirat
3. Experimental results and discussion The thermodynamic data of the three binary were taken from the literature.
systems
4YY
.5.74X+ 0. I24XhTt K)
7YU
Y.YY
3.X66 + U.UY.3I I T( K ,
X3
?OSX,
0.X04+ O.OhXOITI K I
x7x
?Y.Y’J
‘)I2
40.01
- 2.643 + U.OS4YW K , - 3.397 t-O.0429 I T( K,
SU.Un
-4.37h~U.U34SY7~K~
Y.uJ
M,.OO 7U.W X0.w~
- S.663 + O.O?7-!7T~K, - 4.467 +U.O1Y.?3% K, 3.Y31 ?U.U132hTtK)
Y?3 XXS X30
II.729 + O.UUSI47i K ,
X33
X’J.‘r)
In
this
system
the
thermodynamic
properties
were
investigated with an e.m.f. method from Ref. 151. with calorimetric measurements from Ref. 161. and by a vapour pressure method [7,81. The thermodynamic activities were determinrd with a thermal analysis by ltagaki and Yazawa 191 and a torque effusion method [ IO.1 I!. A review of this binary system is given by Moser et al. 112).
,I’,(‘r,:.slI I:I ,~n,rr-s,~~rbln SSNl ??.h70 + 0. I?OlhTf I0.01 1o.UU 3U.OU .w.tn, 10.01 h0.w
K,
Y33
2 I. I X0 + O.UXX747IK ) I4.2YO+U.Of,W?i-(K~
x73 x72 YU3
Il.3.W~O.WXlST~K) h.hY? + O.U3XYST( K, 3.IUY+O.U313XT(K~
Y44 ‘JS2 Y77
K)
Y43
h’J.YY
-I,.? I h i- 0.01 XJOT( K,
YOS
XO.OU YU.UU
-0.410 10.01 Il7T(lo -0.363 + U.W.,XS71 K,
x3x 7YU
I .X4X + 0.023SYTi
(cl) Cit:9~ 2;/ c-,r,r.,-.,cr,ri,,rl
A new and very extensive review of the Cu-Sn system is given by Saunders and Miodownik [ 131. E.m.f. measurements using a solid electrolyte were carried out by Sommer et al. I I41 in the copper-rich solid solution region of this system. New calorimetric investigations of liquid Cu-Sn alloys are reported by Lee et al. 1151. Their data of the mixing enthalpy of liquid Cu-Sn alloys at 997 K are a little more negative than the values recommended by Saunders and Miodownik 1131 and by Hultgren et al. [ 161.
a
and
Tefelske et al. [ 181. We started our investigation from the binary Cu-Sn system by adding zinc. The activity of Zn was measured along four cross-sections with a constant Cu:Sn ratio of
tcrl Ce:.G I:.? w,rr-.wcrhm
AI?,,, = 2F[T(Xlil7),,,.
[ 161 and
by Kowalski
5.01
JXX)o+
0.
I IYhYTt K b
012
IO.01 ?O.UU 30.01
3Y.4YO +O.OXYIS7’( KJ 3?.3UU+U.USYXl7IK,
xxs YU3
272YO+ U.O4I 2X7’(K)
9.5.5
40.0 I
??.47O+U.O3013T( K)
973
SO.02 ha00 7U.UU
I3.970+0.0?533T( K) 6.432 + 0.02 I37T( K ,
9x7 Yw 960
x0.M) ‘H).(w)
I.2?h+lJ.OII?WK, 0. I79 -f U.UWiDT~K,
4.Yl7.0.014lOT(K~
YO? X?I
M. PW,~.
2:l.
I:I.
I:2
tnd
13.
At
A. Mi!.rh
I ,O,‘“,‘,,
0, Allor\
each fixed composition the
temperttture versus e.m.f. curves were straight lines and the e.m.f. is expressed by Eq. (2). In Table I(a) and (b) the parameters (I and h are given for all measured alloys. The activity of Zn in the Cu-Zn system
shows
the Cu:Sn
a negative
2:I
and at Cu:Sn
I:I
content
activity
the
deviation
cross-section it is only of
from
Raouh’s
the deviation slightly zinc
is
negative.
becomes
law.
less
At tin
tl,,,
l&S-
189
IX7
the partial Gibbs free energy. partial enthalpies and pnrtinl entropies are listed. The integral Gibbs free energy ttnd the enthtlpy of mixing for the ternary Cu-Sn-Zn system were cttlculttted using an equation given by Elliott and Chipman 141. The
the
and more
, IW7,
of zinc.
to Sn
positive. The results of our inve+gtion in the ternary system are presented in Fig. I. and in Table 2 the activitie\
.‘I,,
c,m,p
integration
negative
At a higher
more
‘rnd
were
ratio.
value>
with carried and for of
out along
the
Hultqcn
the line
integration et al.
[ 161
of tt constant
constant crlcuktted
used.
The tesults are given in Table 3 and the k-Gibbs free energy curves for Abe ternary system ttre plotted in Fig. 2.
t
AH,,tJ nwl ,
?-MS? IY4S7 I1032 ,,“KS 755 1 i7,,
271’) 243 I 1.150 IY&l 17x’) ,617
?6.1115 11.397 IS.037 I I .7SY Y. 10s h.X-15
A<;,,,IJ nwl
AS,,,11 K
Id) Cu:.G /:.I mnl I:.? uo~~-wc~rion~ ~4, lO2.i ti Cu:Sn 13 0.0s,K) O.lWl O.IYY+ 0.3001
0.0549
0.39YY
0.1015 0.2lhO ,1.3062 Il.4 I ?X
O.JY99
o.s21 S
wiYYY ,~.7wO
O.h170
iY7 I
1751
5.sM
0.7057
2YhS
ISW
4.461
O.7YY9
0.x033
iXh3
XXI
2.hXZ
O.wOI Cu:Sn
O.XY? I
Y7l
IW
I .0x0
I:2
O.,MW O.(r)99
O.,l.M 0. I055
O.?wl O.?YW 0.4OOl
0.3WO
-7XIS
0.5nlxl O.MXM 0.7Ow
O..lY4X ,l.M)lO
SYXS ~J.13,
6Sh X-u IOY3
X.2X0 h.675 S.302
0.70x2
- 1Y3S
Xh?
O.XOOO
OX036
- IX6u -x73
7SY 141
3.71 I Z.SM) O.WI
(6, CI~:SII Cu:Sn
?S7SX IYIZX
IIOY - 746
xOY4 17.%X
0.2026
I3SXI
. ISS
13.123
O.?YhY
I,l3?X
510
o.YO2-l
0.x999 I: I d
?:I
~~rr~,~.s-sc~~lif~~ts or /K.i
l,mAl
K
I:I
O.OSoO 0.1001
O.O3hd lw7XY
2XOYh -21605
O.?OOO U.3OOl)
0. IS62 02.523
-1S7Yl -11713
0.4,lOo 0..5001 0.6lMO
0.3479 OMYY 0.5546
XYXI -67Y-I -5014
-I1Y1 -600 - 357
0.69YY
0.6557
- 3SW
42
ISSO
O.UwO 0.9QOU cusn ?:I 0.050 I O.IOOI
0.7796 0.9Ow
-1IIX -XXX
x7 7”
?.lSS 0.936
-437s -40x7 -27.5x ‘IXX
23. I xx 17.124 I2.7.w 9.310 -- .
7.Sl7 6.0.5s 4..5=1
0.0240 O.OSlh
-31733 -x20
-810s -7620
?3.097 17.203
O.ZOOO 0.3001
O.llW 0.2066
- IX041 - 13414
-6233 -5266
I I .SJZ
0.4001
0.2985
- IO2X.1
-4326
5.813
0.5OCNl 0.6ooo
0.4046 0.5263
-76% -- 5459
-26% - 1241
J.XXX
0.7Oal
0.6447
- 3733
-949
2.722
0.8000
0.7499
-2448
-237
0.9OlM
0.11893
2.16?. 1.009
-998
Cu
C”” h,n*r) cu.S” for IO23 K
7.%5
35
4.123
’ mol ‘,
Table 3. Continued at.% Zn
c,< CI! , .: 0 (HI
(01
.Z/,(~
-S627
-696
4.x20
--414
3.632
> ! -0 n--
I(H)
7.x9-l X.7?)
YSSNJ
-2363
-IX
2. I x4
2.5 110
v-s,?;
.‘I’_‘.‘h
.5z 17x
‘).3(H) ‘J.hYS Y.Y71 10.146
.3’,K1
vsi,
2x7 -10.3 !i25
.:i InI 41 IHI
‘No:
h39
10.2I
Vhh2
4s I”1
v-127
731 7Y9
10. 60 Y.YYS
x.57
9.737
922
9.40s
I IN,2 IOX II4l IOhX 9.50
Y.01 I x.543 7.97 7.253 h.367 5.312
x27
J.OYO
646
2.s70
- h?X -.5X3
7.407 !L%+l 9.212 9.622 9.887
-Vl,Ll
XhYlJ -~x?ls -7h52 -70,
i.c.lXI x0.w 85.W ‘HI(HI
I -62X0 - 9-M -44x5 ‘-33.57
L)S.l,l,
-- IYX3
0.W 5.,x, IO.OU
I:.?
I
AS ,,,, (J K
-4130
L,::i
ihI cl,:slI
‘)
X.5.00
40 : ,
hO MI hi.lXf 70 (H,
(Jmol
90.00
,i,)o
?i.lM)
LH.,,.
h.S?-l
20 InI
iI,,“,
‘)
I-L-l
,.:
IIIIYI
,,,,. (Jm~l
(,.\.N
\<.:..~~.
s IWI
X
,143
I
I
I
IS.00 2”SW)
- IO.527 - 10773
-693 -683 -659
XX,
-IOXYI
-61X
IO.041
30.00
- IOXYY
- 560
IG.iiK,
3s.w
- loxlIx
J0.W
- IOh
-484 - 397
I0.091 9.998
JS.lXl
- 10353
-301
9.826
SO.(X, 55.Ol, hO.Ol,
- YY9S - YSSO -YO,s
-201 -97
9374 9.240
II
x.x23
6.Wl,
-x3x7
I26
X.321
70.00 75.Ou
-- 7h62 --.
24s 3.59
7.721) 7.030
4s3
6.1Y7
496 454 293
5.185 3.927 2.321
X0.00 XSSX, 9o.W
x33 -%X8 -1XlY~ -.x5&l
9s.w
--208,
(‘I) C,r:Su 2:/
<‘NLW.
0.00 5.00 10.00
scvri0n 0, IO?.? K -l(r)41 - 12415 - I32.w
- 36.52 -3x75 - 40x0
7.124 8.34X X.9.54
-4234 --J.sl3
9.331
2.5.00
1427s
-‘Ml?
9.640
30.00
- 14290
-444s
9.62 I
3S.00 40.00
-I-l170 - I3924 - 13558
-4436
9.514
-4365 -4220
Y.344 9.127
ho.00
- I3074 - 12472 -1,752
-3999 -3704 -33.51
X.87 I 8.571 X.212
64.(K)
- 137x0 -14113
IS.00 20.00
45.M) so.00 ss.slLl
‘)
9550
- 10910
-295x
7.773
70.00
-9940
7.5.00 X0.00
-8X34 -7578
- 2540 -2103 -1643
6579 S.802
x5.00 90.w 95.thl
-61.52 -4517 -2.591
-1I.V
4.xX8
-640 --IX3
’ mol
7.234
3.79 I x.54
The minimum is at approximately 48 at.% Cu. 24 at.% Sn and 28 at.% Zn. The data for the binaries Cu-Zn were taken from Gerling and Predel (191 and for Sn-Zn from Moser and Gasior 151. A similar procedure was used to calculate the integral enthalpy of mixing. In this case the data, given by Hultgren et al. [ 161 at 1400 K, were used for the integration constant. The results for the enthalpy are presented in Fig. 3 and given in Table 3. AH,,,i, is negative at the Cu:Sn 2: I and I: I cross-sections. For the I :2 and I :3 cmss-
I‘ ) Cu-.Su 1.1 r m.u rruiw,,t (11 IO?.3 R OSX, s.00 l0.W 15.W)
20.02 2s.w
10233 -llSSX - 122.77 - ,x65,
-I?YlY
-197.5
8.072
-2141
9.20s
-2245 -2327 - 2.384
9.767 IO.099 10.2x4
-13007 - 12984
-2406
10.363
30.00 3s.Ou
-I2844
-2393 -2350
10.353 IO.257
40.00
- I2SY3
-2283
10.079
45.00 50.00 SS.(X,
- 12238 -11785 -1,236
-2193 -2080 -1940
9.819 9.487 9.087
60.00 65.0”
- 10593 -9x52
7osul
-9003
- 1773 -1584 -1380
I?.622 X.082 7.452
75.00
-
-1167
6.710
Fig. 1. Activity uz” of zinc with Pure liquid zinc a a reference state for
-943
5.838
four Cu:Sn cross-sections 2~1. I:I. I:2 and I:3 at 1023 K and for the binary Sn-Zn (Hultgrenet al. [I61 at 750 K) and Cu-Zn (Ceding and Predel 1191 at ll73K).
x0.00
8032 -6915
0.0
0.2
0.4
0.6
0.8
1x9
CU
04
0.2
0.6
%”
08
srl
Acknowledgments Financial support for this investigation was given by the Fondn %ur FGrderung der wissenschaftlichen Forschung under Grant No. P 0!9102-CHE.
121S. Karlhuhw. K.L. Komarek atd A. Mikuh. Z. Mrrdlkd.. 85 (1994) 307.
-5 -
131 R. GefRm.
K.L. Komarek and E. Milkr.
Trwrs. NM&
239 ll%7)
1111. 141 J.F. Elhott and J. Chipman. 1. Am. Chrm. SK.. ISI 2. Mow
and W. G&+x.
161 G.J. Kkppa. 1. Phw
7.3 t 1951) 2a2.
Bd/. Acud. Pd. .%i.. .7/ (1983) 19.
Chum.. 59 (1955) 355.
171 E. Schal and F. Wolf. Z. Mrru//N 50 (19.591 20. 181 E. Scheil and D. Miiller. Z. Mevall~d., 5.7 389.
t I%Z)
191 K. Itagaki and A. Yazawa. Trims. 1. /nsr. Mel.. 18 t 1977) 825.
sectionsthe mixing enthalpyexhibits a changeof sign. The integral enthalpyof mixing for the whole ternary systemis plotted in Fig. 4. For the Cu-Zn system the data of
[IO\ M. Lathrop. Y.A. Chug
Parameswaran and Healy 1201 at 1400 K were used and the values of Hultgren et al. 1161 at 750 K for the Sn-Zn system. Since no data about the liquidus were found in the literature, Table I gives the liquidus temperature for most alloys which was taken from the distinctbreak in the e.m.f. versus temperature curves at the liquidus. The accuracy was estimated to be +7 K. The investigation of the ternary Cu-Sn-Zn system yields a consistent set of thermodynamic data of the liquid alloys, which are useful for the calculation of the ternary phase diagram. The data might also help to improve some
[I?] Z.
industrial processes.
1201 K. Pammeswamn and G. Hedy. Mefd.
and T. Tefelske. Mowrsh.
Chum.. 10.3
(1972) 551. I I I I Y.A. Chang. G.C. Wilhelm. M. Lahmp and L. Gyuk. Arm hfw~ll.. IV(IY71)795. Mow. J. Dulkkwicr. ‘k,qr.. 6 1985) 330.
[IJl
t
F. Sommer. W. Balb;rh (1979) 119.
W. Gaiw
and J. Salava. Bull. Alloy Phase
and B. Pm&l.
Thenwhim.
Arm.
.i.Z
[I51
J.J. Lee. B.J. Kim md W.S. Min. J. A/& Camp.. _mZ (1993) 237. 1161R. Hultgren,RD. Dcwi. D.T. Hawkins. M. Gkiser and K.K. Kelky. Sulwwl
Vulws of the Thwm&tamic
ASM. Metals F’d,
[I71
Properlies #f Liinq
M. Knwalrki and PJ. Spnrer.
J. Phase .&pail.. H ( 1993) 432.
1181 T. Tefelske. Y.A. Chang and R.E. Miller. 2985.
[I91
Allow.
OH. 1973.
U. Ceding and B. PI&I.
Metd.
Trans.. 3 (1972)
Z. Mewrllkd. 71 t 1980) 629. Trans. B. 9 (1978) 657.
: lW7 I IXS-IX9
Thermodynamic properties of liquid Cu-Sn-Zn
alloys
Ming Peng, Adolf Mikula*
Abstract Using an appropriategalvanic cell. the partial free energies of lint in liquid Cu-Sn-Zn alloys were deremuned ins a function of propcnies were obtained liar 40 alloys. Their composition was situated WI four and temperttture. Thermodynamic cross-sectionswith constantratios Cu:Sn of I :3. I:?. I :I and 2: I. Th’ L mtegralfree energy and the intcgnl cnthalpyfor the remary system ill 1023 K were calculated by Gihhs-Duhem integration. concentration
1. Introduction
polished with a tine emery paper and zinc was cleaned
Owing to health concerns and environmental reasons. lead will be replaced in the near future in all solder materials. New lead-free solders must be developed. and for certain applications the ternary X-Sn-Zn alloys could be candidates. We have already investigated the Ag-SnZn [II and Au-Sn-Zn 121 systems. Since copper alloys have excellent electrical properties and high corrosion
prior to its use by melting under vacuum and filtering through quartz wool under a purified argon atmosphere. Copper was used without further puritication. The metals were weighed and sealed in silica capsules under vacuum and melted together at 1300 K tar several days. After heat treatment the alloys were quenched in ice 3 g of each alloy composition water and approximately was used for the e.m.f. measurements.
resistance, they are important materials for different industrial applications. However. data of thermodynamic properties and of the phase diagram are scarce for ternary copper alloys. Thermodynamic data are also needed for the calculation of phase diagrams and for the improvement of industrial processes. In the present investigation the thermodynamic properties of zinc were measured with an e.m.f. method at four cross-sections with a constant Cu:Sn molar ratio of 21. I: I. I:2 and l:3. A Gibbs-Duhem integration was applied to determine the integral thermodynamic properties for the whole ternary system. From the discontinuities in the slope of the e.m.f. versus temperature curves the liquidus temperature for most alloys was determined.
As electrolyte. the euteetic mixture KCI-LiCI with addition of 0.5 ntoF& ZnClz was used. The preparation of the electrolyte and the assembly of the e.m.f. cell are described by Geffken et al. 131. Measurements were carried out on heating and cooling. The heating and cooling rate was 8 to 10 K h-l. Every 50 degrees the temperature was kept constant for a longer period of time to check the stability of the e.m.f. The temperature range of measurements was from the liquidus up to II00 K. The following atrangement for the experiment was used: Zn(l)/Zn
_’(KCI-LiCI)(I)/Cu-Sn-Zn
alloy(l)
Under reversible conditions, the Gibbs free energy change for the reaction is given by
2. Experimental procedure
AC,,
The ternary alloys were prepared from high purity metals (4 N copper from Fischer Scientific Co., NJ; 5 N tin
where F is the Faraday constant (96 486 C mol-‘), E the electromotive force of the cell, R theuniversal gas constant (8.31434J mole’ K-l). T the absolute temperature and a,, the thermodynamic activity of zinc in the ternary alloy, with pure liquid zinc constituent as reference state. At all four cross-sections the e.m.f. versus temperature curves
and zinc from Johnson Matthey GmbH, Vienna,). In order to remove the oxide layer from the surface, Sn was ‘Conespading
author.
0925~8388/97/$17.00 0 1997 Elwier PI/ SO925-8388(96)02575-3
Science S.A. All rights reserved
= - 2FE = RT In (I~”
(1)
This system was evaluated by Hultgren et al. E(mV
) = ,I + h/i K)
(1)
For cxh expsrimrnr two cooling curves were recordrd. The ;pwment hrtwern these two curves was wry good. The drvkuion of the measured r.m.f. values from the tittrd one> \\;a\ ::.0.7 mV ;u 5 and IO at.% Zn. between 50. I and 20. IS IT’S.at ali other compositions. Using the measured values of E. Ihe (I,,, and AC?,,, at a temprramre were calculated. From the temperature drpcndence of E. the partial molar entropy As,,, and were derived. using the following equarnthalpy Xi,,, tions: given
as,,, = ‘FIXlilT)\,,.
= 2hF
(3)
thermodynamic Spencer I I7 I.
re-evaluation
Some information
is given
on this ternary
- El = G,,,
+ 7Is,,,
= - 2oF
The man
(4)
kihhs-Duhem 141 (eq.
(12)
equnrion
given
their
publication)
in
by Elliott
system is given by
l’ahle I Measured e.w.f. datn a,.‘% %n
E m.T.
was
the integral thermodynamic quantities whole ternary system from the e.m.f. data.
- I4.wJ0 + 0. I xixwi K, - 12.MN,+O.l INiT - ,2,1X0+0,077’,27(K, ~~IO.IXOIO.OMW17iK)
7xs xos X6.3 WJ.3 P I ‘J
-Y.?73+0.0,47lXT(K~ --X.-EL) +O.O35477I K,
10
SY.YY
- Y.07’) + U,U?X’JYT( K ,
XX.3
for the
70.00
mX.2X.l t0.023127’~K1
xx0
79.Y’J
-4.Sh.l f 0.013YOTl
~JU.01
-Oh’)3 + U.UUSYhT~ K)
applied
determine
S.“l lO.Ul I’,.‘,‘~ 3U.Ul 3Y,OCJ -l’J.Y’J
and Chip-
KI
Yl7
X43 __
/hJ (‘rr:91 I:2 ~.n~.~.~-s~,~.rirat
3. Experimental results and discussion The thermodynamic data of the three binary were taken from the literature.
systems
4YY
.5.74X+ 0. I24XhTt K)
7YU
Y.YY
3.X66 + U.UY.3I I T( K ,
X3
?OSX,
0.X04+ O.OhXOITI K I
x7x
?Y.Y’J
‘)I2
40.01
- 2.643 + U.OS4YW K , - 3.397 t-O.0429 I T( K,
SU.Un
-4.37h~U.U34SY7~K~
Y.uJ
M,.OO 7U.W X0.w~
- S.663 + O.O?7-!7T~K, - 4.467 +U.O1Y.?3% K, 3.Y31 ?U.U132hTtK)
Y?3 XXS X30
II.729 + O.UUSI47i K ,
X33
X’J.‘r)
In
this
system
the
thermodynamic
properties
were
investigated with an e.m.f. method from Ref. 151. with calorimetric measurements from Ref. 161. and by a vapour pressure method [7,81. The thermodynamic activities were determinrd with a thermal analysis by ltagaki and Yazawa 191 and a torque effusion method [ IO.1 I!. A review of this binary system is given by Moser et al. 112).
,I’,(‘r,:.slI I:I ,~n,rr-s,~~rbln SSNl ??.h70 + 0. I?OlhTf I0.01 1o.UU 3U.OU .w.tn, 10.01 h0.w
K,
Y33
2 I. I X0 + O.UXX747IK ) I4.2YO+U.Of,W?i-(K~
x73 x72 YU3
Il.3.W~O.WXlST~K) h.hY? + O.U3XYST( K, 3.IUY+O.U313XT(K~
Y44 ‘JS2 Y77
K)
Y43
h’J.YY
-I,.? I h i- 0.01 XJOT( K,
YOS
XO.OU YU.UU
-0.410 10.01 Il7T(lo -0.363 + U.W.,XS71 K,
x3x 7YU
I .X4X + 0.023SYTi
(cl) Cit:9~ 2;/ c-,r,r.,-.,cr,ri,,rl
A new and very extensive review of the Cu-Sn system is given by Saunders and Miodownik [ 131. E.m.f. measurements using a solid electrolyte were carried out by Sommer et al. I I41 in the copper-rich solid solution region of this system. New calorimetric investigations of liquid Cu-Sn alloys are reported by Lee et al. 1151. Their data of the mixing enthalpy of liquid Cu-Sn alloys at 997 K are a little more negative than the values recommended by Saunders and Miodownik 1131 and by Hultgren et al. [ 161.
a
and
Tefelske et al. [ 181. We started our investigation from the binary Cu-Sn system by adding zinc. The activity of Zn was measured along four cross-sections with a constant Cu:Sn ratio of
tcrl Ce:.G I:.? w,rr-.wcrhm
AI?,,, = 2F[T(Xlil7),,,.
[ 161 and
by Kowalski
5.01
JXX)o+
0.
I IYhYTt K b
012
IO.01 ?O.UU 30.01
3Y.4YO +O.OXYIS7’( KJ 3?.3UU+U.USYXl7IK,
xxs YU3
272YO+ U.O4I 2X7’(K)
9.5.5
40.0 I
??.47O+U.O3013T( K)
973
SO.02 ha00 7U.UU
I3.970+0.0?533T( K) 6.432 + 0.02 I37T( K ,
9x7 Yw 960
x0.M) ‘H).(w)
I.2?h+lJ.OII?WK, 0. I79 -f U.UWiDT~K,
4.Yl7.0.014lOT(K~
YO? X?I
M. PW,~.
2:l.
I:I.
I:2
tnd
13.
At
A. Mi!.rh
I ,O,‘“,‘,,
0, Allor\
each fixed composition the
temperttture versus e.m.f. curves were straight lines and the e.m.f. is expressed by Eq. (2). In Table I(a) and (b) the parameters (I and h are given for all measured alloys. The activity of Zn in the Cu-Zn system
shows
the Cu:Sn
a negative
2:I
and at Cu:Sn
I:I
content
activity
the
deviation
cross-section it is only of
from
Raouh’s
the deviation slightly zinc
is
negative.
becomes
law.
less
At tin
tl,,,
l&S-
189
IX7
the partial Gibbs free energy. partial enthalpies and pnrtinl entropies are listed. The integral Gibbs free energy ttnd the enthtlpy of mixing for the ternary Cu-Sn-Zn system were cttlculttted using an equation given by Elliott and Chipman 141. The
the
and more
, IW7,
of zinc.
to Sn
positive. The results of our inve+gtion in the ternary system are presented in Fig. I. and in Table 2 the activitie\
.‘I,,
c,m,p
integration
negative
At a higher
more
‘rnd
were
ratio.
value>
with carried and for of
out along
the
Hultqcn
the line
integration et al.
[ 161
of tt constant
constant crlcuktted
used.
The tesults are given in Table 3 and the k-Gibbs free energy curves for Abe ternary system ttre plotted in Fig. 2.
t
AH,,tJ nwl ,
?-MS? IY4S7 I1032 ,,“KS 755 1 i7,,
271’) 243 I 1.150 IY&l 17x’) ,617
?6.1115 11.397 IS.037 I I .7SY Y. 10s h.X-15
A<;,,,IJ nwl
AS,,,11 K
Id) Cu:.G /:.I mnl I:.? uo~~-wc~rion~ ~4, lO2.i ti Cu:Sn 13 0.0s,K) O.lWl O.IYY+ 0.3001
0.0549
0.39YY
0.1015 0.2lhO ,1.3062 Il.4 I ?X
O.JY99
o.s21 S
wiYYY ,~.7wO
O.h170
iY7 I
1751
5.sM
0.7057
2YhS
ISW
4.461
O.7YY9
0.x033
iXh3
XXI
2.hXZ
O.wOI Cu:Sn
O.XY? I
Y7l
IW
I .0x0
I:2
O.,MW O.(r)99
O.,l.M 0. I055
O.?wl O.?YW 0.4OOl
0.3WO
-7XIS
0.5nlxl O.MXM 0.7Ow
O..lY4X ,l.M)lO
SYXS ~J.13,
6Sh X-u IOY3
X.2X0 h.675 S.302
0.70x2
- 1Y3S
Xh?
O.XOOO
OX036
- IX6u -x73
7SY 141
3.71 I Z.SM) O.WI
(6, CI~:SII Cu:Sn
?S7SX IYIZX
IIOY - 746
xOY4 17.%X
0.2026
I3SXI
. ISS
13.123
O.?YhY
I,l3?X
510
o.YO2-l
0.x999 I: I d
?:I
~~rr~,~.s-sc~~lif~~ts or /K.i
l,mAl
K
I:I
O.OSoO 0.1001
O.O3hd lw7XY
2XOYh -21605
O.?OOO U.3OOl)
0. IS62 02.523
-1S7Yl -11713
0.4,lOo 0..5001 0.6lMO
0.3479 OMYY 0.5546
XYXI -67Y-I -5014
-I1Y1 -600 - 357
0.69YY
0.6557
- 3SW
42
ISSO
O.UwO 0.9QOU cusn ?:I 0.050 I O.IOOI
0.7796 0.9Ow
-1IIX -XXX
x7 7”
?.lSS 0.936
-437s -40x7 -27.5x ‘IXX
23. I xx 17.124 I2.7.w 9.310 -- .
7.Sl7 6.0.5s 4..5=1
0.0240 O.OSlh
-31733 -x20
-810s -7620
?3.097 17.203
O.ZOOO 0.3001
O.llW 0.2066
- IX041 - 13414
-6233 -5266
I I .SJZ
0.4001
0.2985
- IO2X.1
-4326
5.813
0.5OCNl 0.6ooo
0.4046 0.5263
-76% -- 5459
-26% - 1241
J.XXX
0.7Oal
0.6447
- 3733
-949
2.722
0.8000
0.7499
-2448
-237
0.9OlM
0.11893
2.16?. 1.009
-998
Cu
C”” h,n*r) cu.S” for IO23 K
7.%5
35
4.123
’ mol ‘,
Table 3. Continued at.% Zn
c,< CI! , .: 0 (HI
(01
.Z/,(~
-S627
-696
4.x20
--414
3.632
> ! -0 n--
I(H)
7.x9-l X.7?)
YSSNJ
-2363
-IX
2. I x4
2.5 110
v-s,?;
.‘I’_‘.‘h
.5z 17x
‘).3(H) ‘J.hYS Y.Y71 10.146
.3’,K1
vsi,
2x7 -10.3 !i25
.:i InI 41 IHI
‘No:
h39
10.2I
Vhh2
4s I”1
v-127
731 7Y9
10. 60 Y.YYS
x.57
9.737
922
9.40s
I IN,2 IOX II4l IOhX 9.50
Y.01 I x.543 7.97 7.253 h.367 5.312
x27
J.OYO
646
2.s70
- h?X -.5X3
7.407 !L%+l 9.212 9.622 9.887
-Vl,Ll
XhYlJ -~x?ls -7h52 -70,
i.c.lXI x0.w 85.W ‘HI(HI
I -62X0 - 9-M -44x5 ‘-33.57
L)S.l,l,
-- IYX3
0.W 5.,x, IO.OU
I:.?
I
AS ,,,, (J K
-4130
L,::i
ihI cl,:slI
‘)
X.5.00
40 : ,
hO MI hi.lXf 70 (H,
(Jmol
90.00
,i,)o
?i.lM)
LH.,,.
h.S?-l
20 InI
iI,,“,
‘)
I-L-l
,.:
IIIIYI
,,,,. (Jm~l
(,.\.N
\<.:..~~.
s IWI
X
,143
I
I
I
IS.00 2”SW)
- IO.527 - 10773
-693 -683 -659
XX,
-IOXYI
-61X
IO.041
30.00
- IOXYY
- 560
IG.iiK,
3s.w
- loxlIx
J0.W
- IOh
-484 - 397
I0.091 9.998
JS.lXl
- 10353
-301
9.826
SO.(X, 55.Ol, hO.Ol,
- YY9S - YSSO -YO,s
-201 -97
9374 9.240
II
x.x23
6.Wl,
-x3x7
I26
X.321
70.00 75.Ou
-- 7h62 --.
24s 3.59
7.721) 7.030
4s3
6.1Y7
496 454 293
5.185 3.927 2.321
X0.00 XSSX, 9o.W
x33 -%X8 -1XlY~ -.x5&l
9s.w
--208,
(‘I) C,r:Su 2:/
<‘NLW.
0.00 5.00 10.00
scvri0n 0, IO?.? K -l(r)41 - 12415 - I32.w
- 36.52 -3x75 - 40x0
7.124 8.34X X.9.54
-4234 --J.sl3
9.331
2.5.00
1427s
-‘Ml?
9.640
30.00
- 14290
-444s
9.62 I
3S.00 40.00
-I-l170 - I3924 - 13558
-4436
9.514
-4365 -4220
Y.344 9.127
ho.00
- I3074 - 12472 -1,752
-3999 -3704 -33.51
X.87 I 8.571 X.212
64.(K)
- 137x0 -14113
IS.00 20.00
45.M) so.00 ss.slLl
‘)
9550
- 10910
-295x
7.773
70.00
-9940
7.5.00 X0.00
-8X34 -7578
- 2540 -2103 -1643
6579 S.802
x5.00 90.w 95.thl
-61.52 -4517 -2.591
-1I.V
4.xX8
-640 --IX3
’ mol
7.234
3.79 I x.54
The minimum is at approximately 48 at.% Cu. 24 at.% Sn and 28 at.% Zn. The data for the binaries Cu-Zn were taken from Gerling and Predel (191 and for Sn-Zn from Moser and Gasior 151. A similar procedure was used to calculate the integral enthalpy of mixing. In this case the data, given by Hultgren et al. [ 161 at 1400 K, were used for the integration constant. The results for the enthalpy are presented in Fig. 3 and given in Table 3. AH,,,i, is negative at the Cu:Sn 2: I and I: I cross-sections. For the I :2 and I :3 cmss-
I‘ ) Cu-.Su 1.1 r m.u rruiw,,t (11 IO?.3 R OSX, s.00 l0.W 15.W)
20.02 2s.w
10233 -llSSX - 122.77 - ,x65,
-I?YlY
-197.5
8.072
-2141
9.20s
-2245 -2327 - 2.384
9.767 IO.099 10.2x4
-13007 - 12984
-2406
10.363
30.00 3s.Ou
-I2844
-2393 -2350
10.353 IO.257
40.00
- I2SY3
-2283
10.079
45.00 50.00 SS.(X,
- 12238 -11785 -1,236
-2193 -2080 -1940
9.819 9.487 9.087
60.00 65.0”
- 10593 -9x52
7osul
-9003
- 1773 -1584 -1380
I?.622 X.082 7.452
75.00
-
-1167
6.710
Fig. 1. Activity uz” of zinc with Pure liquid zinc a a reference state for
-943
5.838
four Cu:Sn cross-sections 2~1. I:I. I:2 and I:3 at 1023 K and for the binary Sn-Zn (Hultgrenet al. [I61 at 750 K) and Cu-Zn (Ceding and Predel 1191 at ll73K).
x0.00
8032 -6915
0.0
0.2
0.4
0.6
0.8
1x9
CU
04
0.2
0.6
%”
08
srl
Acknowledgments Financial support for this investigation was given by the Fondn %ur FGrderung der wissenschaftlichen Forschung under Grant No. P 0!9102-CHE.
121S. Karlhuhw. K.L. Komarek atd A. Mikuh. Z. Mrrdlkd.. 85 (1994) 307.
-5 -
131 R. GefRm.
K.L. Komarek and E. Milkr.
Trwrs. NM&
239 ll%7)
1111. 141 J.F. Elhott and J. Chipman. 1. Am. Chrm. SK.. ISI 2. Mow
and W. G&+x.
161 G.J. Kkppa. 1. Phw
7.3 t 1951) 2a2.
Bd/. Acud. Pd. .%i.. .7/ (1983) 19.
Chum.. 59 (1955) 355.
171 E. Schal and F. Wolf. Z. Mrru//N 50 (19.591 20. 181 E. Scheil and D. Miiller. Z. Mevall~d., 5.7 389.
t I%Z)
191 K. Itagaki and A. Yazawa. Trims. 1. /nsr. Mel.. 18 t 1977) 825.
sectionsthe mixing enthalpyexhibits a changeof sign. The integral enthalpyof mixing for the whole ternary systemis plotted in Fig. 4. For the Cu-Zn system the data of
[IO\ M. Lathrop. Y.A. Chug
Parameswaran and Healy 1201 at 1400 K were used and the values of Hultgren et al. 1161 at 750 K for the Sn-Zn system. Since no data about the liquidus were found in the literature, Table I gives the liquidus temperature for most alloys which was taken from the distinctbreak in the e.m.f. versus temperature curves at the liquidus. The accuracy was estimated to be +7 K. The investigation of the ternary Cu-Sn-Zn system yields a consistent set of thermodynamic data of the liquid alloys, which are useful for the calculation of the ternary phase diagram. The data might also help to improve some
[I?] Z.
industrial processes.
1201 K. Pammeswamn and G. Hedy. Mefd.
and T. Tefelske. Mowrsh.
Chum.. 10.3
(1972) 551. I I I I Y.A. Chang. G.C. Wilhelm. M. Lahmp and L. Gyuk. Arm hfw~ll.. IV(IY71)795. Mow. J. Dulkkwicr. ‘k,qr.. 6 1985) 330.
[IJl
t
F. Sommer. W. Balb;rh (1979) 119.
W. Gaiw
and J. Salava. Bull. Alloy Phase
and B. Pm&l.
Thenwhim.
Arm.
.i.Z
[I51
J.J. Lee. B.J. Kim md W.S. Min. J. A/& Camp.. _mZ (1993) 237. 1161R. Hultgren,RD. Dcwi. D.T. Hawkins. M. Gkiser and K.K. Kelky. Sulwwl
Vulws of the Thwm&tamic
ASM. Metals F’d,
[I71
Properlies #f Liinq
M. Knwalrki and PJ. Spnrer.
J. Phase .&pail.. H ( 1993) 432.
1181 T. Tefelske. Y.A. Chang and R.E. Miller. 2985.
[I91
Allow.
OH. 1973.
U. Ceding and B. PI&I.
Metd.
Trans.. 3 (1972)
Z. Mewrllkd. 71 t 1980) 629. Trans. B. 9 (1978) 657.