Phase Diagram Study and Thermodynamic Modeling of the ZnO–ZrO ₂ –SiO ₂ System

ABSTRACT The phase diagram of the ZnO–ZrO 2 –SiO 2 system was experimentally studied at 1500°C and 1600°C by classical equilibration and quenching method followed by X‐ray diffraction (XRD) phase analysis and electron probe micro‐analysis (EPMA). Sealed Pt crucible was utilized to prevent the volatile loss of ZnO during high temperature phase equilibrium experiments. The general feature of the phase diagram of the ZnO–ZrO 2 –SiO 2 system was revealed for the first time. No ternary stoichiometric compound was found in the ZnO–ZrO 2 –SiO 2 system at 1500°C and 1600°C, and 0.015–0.058 mol fr. of ZnO solubility was found in tetragonal‐ZrO 2 . Based on the present experimental data, the thermodynamic modeling of the ternary system was conducted based on the CALculation of PHAse Diagram (CALPHAD) method.