Thermodynamic assessment of the BaO - TiO2 quasibinary system

Experimental data from the literature on the BaO-TiO2 quasibinary system have been evaluated to assess the thermodynamic parameters of all the stable phases by means of the CALPHAD (CALculation of PHAse Diagram) method. The two-sublattice ionic solution model was used to describe the liquid phase, while the compound energy model was applied to describe the high-temperature forms of BaTiO3. Other compounds were treated as stoichiometric phases. The assessment was conducted using the Thermo-calc software package and a set of parameters was given. Calculated equilibrium phase diagrams and thermochemical properties compared with the experimental data are presented. There is a good agreement between the calculations and the experimental data. Some contradictions are pointed out and discussed.