Thermodynamic Description of the Gd-Sb and Gd-Bi-Sb Systems

Jinming Liu, Xiaoyang Chen,

Abstract

The thermodynamic modeling and optimization of the Gd-Sb and Gd-Bi-Sb systems were critically carried out by means of the CALPHAD (CALculation of PHAse Diagram) technique. The solution phases, liquid, bcc, rhomb and hcp(Gd) were described by the substitutional solution model. The compounds, β-Gd5(Bi, Sb)3, γ-Gd4(Bi, Sb)4, δ-Gd(Bi, Sb), δ′-Gd(Bi, Sb), ε-Gd16Sb39 and GdBi2 were treated as the formulae (Gd)m/m+n(Gd, Bi, Sb)n/m+n using two sublattice model in the Gd-Bi-Sb system. A self-consistent thermodynamic description of the Gd-Sb and Gd-Bi-Sb system were developed. The isothermal section at 300 K for the Gd-Bi-Sb system in the literature were reproduced in the present work.