Phase diagram study and thermodynamic modeling of the Na ₂ O–Al ₂ O ₃ –ZrO ₂ system

The phase diagram of the Na 2 O–Al 2 O 3 –ZrO 2 system was experimentally studied at 1500°C–1650°C by a classical equilibration/quenching method and differential thermal analysis followed by X‐ray diffraction phase analysis and electron probe micro‐analysis. A sealed Pt crucible was utilized to prevent the volatile loss of Na 2 O during high‐temperature phase equilibrium experiments and the hydration upon quenching. The phase diagram of the Na 2 O–Al 2 O 3 –ZrO 2 system was revealed for the first time. Based on the present experimental data and available binary modeling results in literature, the thermodynamic modeling of the ternary system was performed using the Calculation of Phase Diagram method and the phase diagram of the entire the Na 2 O–Al 2 O 3 –ZrO 2 system was constructed and the optimized thermodynamic properties for all solids and liquid phase within the ternary system were obtained.