LAUSR

The CAlculation of PHAse Diagram (CALPHAD) technique is used in the critical remodeling of the Cd–Gd system. On the basis of a new experiment in literature, the excess Gibbs energies of the solution phase expression (liquid, bcc, and hcp_A3) are described using the Redlich–Kister equation. Intermetallic compounds (α-Cd2Gd, β-Cd2Gd, and Cd45Gd11), which exhibit a homogeneity range, are treated as a two-sublattice model. Four compounds (Cd3Gd, Cd58Gd13, Cd6Gd, and Cd8Gd) are treated as stoichiometric compounds. Two Calphad-type thermodynamic descriptions are developed for the CdGd and bcc. Model I is to model the compound CdGd and bcc-Gd separately. Model II is to use the formula (Cd,Gd)0.5(Cd,Gd)0.5(Va)3 to describe the compound CdGd with a CsCl-type structure (B2) and cope with the disorder–order transition from bcc-A2 to bcc-B2. The present work displays that two eutectic reactions, five peritectic reactions, one peritectoid reaction, one eutectoid reaction, one polymorphic transformation, and one congruent reaction are observed in the Cd–Gd system.