Assessment of thermodynamic parameters in the system ZrO2-Y2O3-Al2O3

The thermodynamic parameters have been assessed for the systems of ZrO2-Y2O3, ZrO2-Al2O3 and ZrO2-Y2O3-Al2O3 using the Calphad technique. The solid solutions are described by the compound energy formalism. A two-sublattice ionic liquid model is used to describe the liquid phase. The phase diagrams of the ZrO2-Y2O3 and ZrO2-Al2O3 and Y2O3-Al2O3 systems are in fairly good agreement with phase equilibrium data. Isothermal sections of the phase diagram of the ZrO2-Y2O3-Al2O3 system at subsolidus conditions are calculated. Introducing ternary interactions in the liquid phase results in a better fit to experimental data of the liquidus surface and isoplethal sections.