Phase equilibria in Y---Sr---Cu---O pseudoternary system at elevated oxygen pressure of 200 bar

Abstract

We report the investigations on phase relations and phase compatibilities in Y-Sr-Cu-O pseudoternary at a temperature of 980° C and P(O₂)=200 bar. There is no evidence of a single phase quarternary compound. The SrO-CuO pseudobinary shows a remarkable difference as compared to its analog at 1 bar. Highly oxidized phases such as Sr₂CuO_3+δ and Sr₁₄Cu₂4O₄₁ are found to be stabilized under an oxidizing atmosphere of 200 bar. Sr₁₄Cu₂₄O₄₁ has a solid solubility of Y for Sr up to a solubility limit of 30%. Partial melting is observed near the SrO vertex, where the presence of an unidentified quarternary peritectic is suggested by the appearance of additional XRD peaks.