A thermodynamic assessment of the Bi–Mg–Sn ternary system

A complete thermodynamic description of the Bi–Mg–Sn ternary system was obtained by means of the CALPHAD (CALculation of PHAse Diagram) technique. The solution phases, Rhomb, Bct_A5 and Hcp_A3, are modeled with Redlich–Kister equation. The associate model has been used to describe the liquid phase with the constituents of the species Bi, Bi2Mg3, Mg, Mg2Sn and Sn. The non-stoichiometric compounds Mg2Sn and α-Bi2Mg3 as well as its high temperature variant β-Bi2Mg3 were described by the sublattice models (Bi,Mg)2(Bi,Sn)1, (Bi,Sn,Va)2Mg3 and (Bi,Sn)1(Bi,Sn,Va)3Mg6, respectively. The Bi–Mg–Sn ternary system has been modeled thermodynamically for the first time and the calculated phase equilibrium relations and thermochemical properties are consistent with the experimental results available in literatures.