Phase equilibrium relations in the V2O3-La2O3 system

Phase equilibrium relations in the V2O3-La2O3 system were investigated by X-ray powder diffraction and metallographic techniques. Binary mixtures, prepared from high-purity V2O3 and La2O3 powders, were equilibrated at 16000C and then arc-melted under a partial pressure of argon. The specimens were heat-treated at various predetermined temperatures for prolonged periods and the phases present were identified by reflected-light microscopy and X-ray powder diffraction. The system consists of only one binary compound LaVO3. A eutectic between V2O3 and LaVO3 was established at 17500C and 19 mol% La2O3 and also between LaVO3 and La2O3 at 17650C and 75 mol% La2O3. No appreciable solid solubility was detected in the system. (author)