Thermodynamic investigation of ZrO2-BaO system

Thermodynamic description of ZrO2-BaO system was developed using the available experimental information. Special attention was paid to the modelling of the perovskite phase BaZrO3 by a temperature-dependent polynomial to fit the experimental thermodynamic properties. The liquid phases, Css (cubic ZrO2 solid solution) and Tss (tetragonal ZrO2 solid solution) were modelled with Redlich-Kister formula. The compounds Ba2ZrO4 and Ba3Zr2O7 were treated as stoichiometric phases and the BaOss and Mss (halite BaO and monoclinic ZrO2 solid solutions) were treated as pure compounds. Comparisons between the calculated and the measured phase diagram as well as the thermodynamic quantities indicate that the most reliable experimental information is satisfactorily accounted for by the present thermodynamic calculation.