Two Unknown Phases and Platinum Solubility in Y-Ba-Cu-O System

Two unknown phases which were found in a process of studying a phase diagram of the Y-Ba-Cu-O system were investigated. Platinum solubility in Y-Ba-Cu-O system was examined in order to see whether those unknown phases were related to platinum, which was used as a vessel plate in quenching experiments. Platinum was found to dissolve easily in the Y-Ba-Cu-O system with a solubility of as much as 14% in the temperature range of 900 to 950°C. It is concluded that at least one of those unknown phases is related to platinum.