Thermodynamic properties of Eu-Pt and Al-Eu-Pt melts

The partial and integral enthalpies of mixing of Eu-Pt melts were determined by calorimetry at 1300 K in the composition range 0 < x Pt < 0.36. The first partial enthalpy of mixing of Pt was found to be −171 ± 2 kJ/mol. The thermodynamic properties of the Eu-Pt melts were modeled in terms of ideal associated solution theory in wide composition and temperature ranges. The results indicate that the activities of the components have large negative deviations from Raoult’s law and that the integral Gibbs energy and enthalpy of mixing have a minimum near x Pt = 0.7. The enthalpy and excess Gibbs energy of mixing of Al-Eu-Pt ternary melts were modeled using our and others’ data and Kohler’s equation.