Subsolidus Phase Relations of the CoO-CuO-SrO System.

The subsolidus phase relations of the CoO-CuO-SrO system were investigated in air. The samples were equilibrated at 900 °C. The pseudo-ternary section contains three stoichiometric binary oxide phases (SrCuO, SrCuO and SrCuO) and a binary oxide solid solution: SrCoO (0 ≤ x ≤ 0.36). Two binary phases extend into the ternary system forming solid solutions, i.e., SrCuCoO (0 ≤ x ≤ 5) and SrCoCuO (0 ≤ x ≤ 0.36, 0 ≤ y ≤ 1.0). The SrCoO solid solution was found to undergo a phase separation into a mixture of SrCoO and SrCoO upon annealing at 600 °C. This transformation is reversible. [ABSTRACT FROM AUTHOR]