CALPHAD modeling of the La2O3–Y 2O3 system

Using the CALPHAD approach, we model the La2O3–Y 2O3 system as a pseudo-binary section of the La–Y–O ternary system. The descriptions of two binary sub-systems, La–O and Y–O, are taken from previous assessments with revision. The experimental data on the La2O3–Y 2O3 system are reviewed and the parameters related to the La2O3–Y 2O3 section are optimized. Our calculated La2O3–Y 2O3 phase diagram agrees well with most experimental data. Further experimental efforts are necessary to verify the phase relations at temperatures below 2000 K.