Pb-FREE SOLDERS: ESTIMATING OF SOME PHYSICOCHEMICAL AND THERMODYNAMIC PROPERTIES OF TERNARY Cu-Ag-In SYSTEM

The surface tension and viscosity in the liquid Cu-Ag-In ternary alloys have been estimated using Muggianu and Toop geometric models and Seetharaman–Sichen equations, respectively along a cross-section of xAg/xIn=1∕2, 1/1 and 2/1. The surface tension has also been estimated using Butler equation. In addition, the enthalpies of the same ternary alloys have been predicted at different temperatures along five cross-sections xCu/xIn=1∕3, 1/2, 1/1, 2/1 and 3/1 using Kohler, Toop and Chou models. The geometric models are used in this work in order to verify their effectiveness since they are considered as the most widespread theoretical models used for metallic alloys. The estimated values obtained show that the surface tension decreases with increasing temperature for the all studied models and equations and increase with increasing copper-composition, except for few Cu-compositions where an opposite tendency is observed. It should be noted that the surface tension has a negative and positive temperature coefficient (dσ/dT). The viscosity decreases with increasing temperature but increases with increasing copper-compositions. The calculated surface tension and enthalpy of mixing of the investigated system are compared with the reachable experimental data and a relatively excellent accord was obtained.