Thermodynamic modeling of the Bi–Ca and Bi–Zr systems

Abstract

Abstract In the literature, there are no reliable thermodynamic descriptions for the Bi–Ca and Bi–Zr systems. In the present work, by means of the CALPHAD (calculation of phase diagrams) method, the thermodynamic assessments of the Bi–Ca and Bi–Zr systems were carried out based on the available data. The Gibbs energies of the liquid, bcc and hcp phases in these two binary systems were described by the substitutional solution model with the Redlich–Kister equation, and the intermetallic compounds (αBi10Ca11, βBi10Ca11, Bi3Ca5, Bi2Zr, Bi1.62Zr, BiZr, Bi2Zr3, and BiZr2 phases) were treated as stoichiometric phases. A good agreement between the calculated results and experimental data is obtained for both systems. The presently obtained thermodynamic parameters for the Bi–Ca and Bi–Zr systems are of interest for the development of Bi-based alloys.