Thermodynamic assessments of the V–Ge and V–Pt systems

Abstract

The V–Ge and V–Pt binary systems have been thermodynamically assessed by using the CALPHAD ( Calculation of Phase Diagrams) approach on the basis of the experimental data including the thermodynamic properties and phase equilibria. Gibbs free energies of the solution phases (liquid, fcc, bcc and diamond) were modeled by the subregular solution model with the Redlich–Kister formula, and those of the intermetallic compounds (V 3Ge, V 5Ge 3, V 11Ge 8, V 17Ge 31, PtV 3, PtV, Pt 2V and Pt 3V) in these two binary systems were described by the sublattice model. A proper set of thermodynamic parameters has been derived for describing the Gibbs free energies of each phase in the V–Ge and V–Pt systems. An agreement between the calculated results and experimental data is obtained.