Composition Dependences of Thermodynamical Properties Associated with PbFree Ternary, Quaternary, and Quinary Solder Systems

Abstract—In the present study, Chou’s General Solution Model (GSM) has been used to predict the
enthalpy and partial enthalpies of mixing of the liquid Ag–In–Sn ternary, Ag–In–Sn–Zn quaternary, and
Ag–Au–In–Sn–Zn quinary systems. These are of technical importance to optimize leadfree solder alloys,
in selected crosssections: xIn/xSn = 0.5/0.5 (ternary), Au–In0.1–Sn0.8–Zn0.1, Ag–In0.1–Sn0.8–Zn0.1 (qua
ternary), and t = xAu/xIn = 1, xIn = xSn = xZn (quinary) at 1173, 773, and 773 K, respectively. Moreover, the
activity of In content in the ternary alloy system Ag–In–Sn has been calculated and its result is compared
with that determined from the experiment, while the activities of Ag contents associated with the alloys men
tioned above have been calculated. The other traditional models such as of Colinet, Kohler, Muggianu, Toop,
and Hillert are also included in calculations. Comparing those calculated from the proposed GSM with those
determined from experimental measurements, it is seen that this model becomes considerably realistic in
computerization for estimating thermodynamic properties in multicomponent systems.