Pb-free solders: Experimental and calculated enthalpy of mixing of the liquid Au–In–Sn–Zn quaternary system

•First paper providing partial enthalpy of mixing determined by calorimetry for Au–In–Sn–Zn.•First paper providing integral enthalpy of mixing measured by calorimetry for Au–In–Sn–Zn.•First paper providing integral enthalpy of mixing calculated using a geometric models for Au–In–Sn–Zn.

The partial and the integral enthalpies of mixing of liquid Au–In–Sn–Zn quaternary alloys have been measured at 500 °C along five ternary sections: In0.800Sn0.100Zn0.100, In0.550Sn0.225Zn0.225, In0.100Sn0.800Zn0.100, In0.450Sn0.450Zn0.100, and In0.225Sn0.550Zn0.225. In addition, using Kohler, Muggianu and Toop geometric models, the enthalpies of mixing were calculated and compared to the experimental one.