Phase diagram of the ZrO 2–Gd 2O 3–Al 2O 3 system

Abstract

Isothermal sections of the phase diagram for the ZrO 2–GdO 3/2–AlO 3/2 system have been constructed based on experimental phase equilibrium data at 1250 and 1650 °C. They are in a good agreement with calculations which have also been performed in the present study. The liquidus and solidus surfaces have been experimentally determined. The temperature of the eutectic reaction liquid = Al 2O 3 + fluorite + GdAlO 3 was measured using differential thermal analysis (DTA) to be 1662 °C. The liquidus surface calculated in this work using a non-zero ternary interaction parameter in the liquid phase agrees with the experimental data. A thermodynamic description of the ZrO 2–GdO 3/2–AlO 3/2 system based on an ionic sublattice model for the solid and liquid phases consistent with the experimental data has been derived.