Thermodynamic assessments of the Ho–X (X: Cu, Mo, V) systems

The thermodynamic assessments of the Ho–X (X: Cu, Mo, V) systems have been carried out by using the CALPHAD (Calculation of Phase Diagrams) method based on available experimental data including thermodynamic properties and phase equilibria. Gibbs free energies of the solution phases (liquid, hcp, fcc and bcc phase) were described by the subregular solution model with the Redlich–Kister formula, and those of the intermetallic compounds (αCu5Ho, βCu5Ho, Cu9Ho2, Cu7Ho2, Cu2Ho and CuHo compound) in the Cu–Ho system were described by the sublattice model. Good agreement between the present calculated results and experimental data was obtained.