The determination of the integral enthalpies of mixing of liquid Au–In–Sn alloys and the enthalpy of formation of the Au4In3Sn3 compound

With a view to modelling the Au–In–Sn alloy system, the enthalpies of mixing of liquid Au–In–Sn alloys have been measured as a function of Au content by drop calorimetry at 609 °C for constant In:Sn ratios of 1:1, 1:3 and 3:1. For each of the three sections studied, the enthalpies of mixing were exothermic. In addition, the enthalpy of formation of the ternary Au4In3Sn3 at 298 K was measured both by direct-reaction calorimetry and by tin-solution calorimetry.