Thermodynamic reassessment of Ga-Hg and Mg-Hg systems

Abstract

The Ga-Hg binary system was thermodynamically assessed by the CALPHAD method, but only configuration contributions were considered to the entropy of the liquid. The Mg-Hg binary system has not been assessed yet. In the assessments of the Ga-Hg and Mg-Hg binary systems, solutions including liquid and hcp (Mg) were treated as substitution solutions, of which the excess Gibbs energies were formulated with the Relich-Kister polynomial. The intermetallic phases in the Mg-Hg binary system, Mg₃Hg, Mg₅Hg₂, Mg₂Hg, Mg₅Hg₃, MgHg, and MgHg₂, were described as stoichiometric compounds. Based on the reported experimental data and thermodynamic properties of the phase diagram, sets of self-consistent parameters describing all phases in the Ga-Hg and the Mg-Hg binary systems were obtained.

Keywords

Ga-Hg system / Mg-Hg system / intermetallic phases / thermodynamic assessment / phase diagram / CALPHAD