Thermodynamic assessments of the Al–Th and Th–Zn systems

Abstract

The phase diagrams of the Al–Th and Th–Zn systems have been evaluated by using the Calculation of Phase Diagrams (CALPHAD) method with the experimental data including the phase equilibria and thermodynamic properties. The Gibbs free energies of the liquid, bcc and hcp phases were described by the subregular solution model with the Redlich–Kister equation, and those of the stoichiometric compounds of the Th2Al, Th3Al2, ThAl, Th2Al3, ThAl2, ThAl3, Th2Al7, Th2Zn, ThZn2, ThZn4 and Th2Zn17 were described by the two-sublattice model. The calculated phase equilibria and thermodynamic properties are in good agreement with the experimental data.