Phase relations in the ZrO2–Nd2O3–Y2O3–Al2O3 system: Experimental study and thermodynamic modeling

The Nd2O3–Al2O3 and ZrO2–Nd2O3–Al2O3 systems were simultaneously re-assessed to reproduce experimental data from present study and literature. Phase relations in the Nd2O3–Y2O3–Al2O3 system were investigated by XRD, electron microscopy and DTA for the first time. Invariant reaction in solid phases B + YAM = NdAlO3 + C was determined to occur at 1863 K. The eutectic reaction liquid = YAG + NdAlO3 + Al2O3 was determined to occur at 2042 K and composition Al2O3–10 mol.% Nd2O3–13 mol.% Y2O3. The obtained data were used to assess thermodynamic parameters of this system. Isothermal sections were calculated in the range 1523–1923 K. Liquidus surface of the Nd2O3–Y2O3–Al2O3 system was calculated. The derived databases were combined with already available descriptions of the ZrO2–Nd2O3–Y2O3 and ZrO2–Y2O3–Al2O3 systems into four-oxide database.