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.