Phase Equilibria in the System SrO-CdO-V2O5

• Published in: Journal of the American Ceramic Society 1972-01, Vol.55 (10), p.500-503
• Main Author: BROWN JR, JESSE J.
• Format: Article
• Language: English
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/j.1151-2916.1972.tb13415.x

Phase equilibria in the system SrO‐CdO‐V2O5 in air were established from data obtained by DTA, quenching, and high‐temperature solid‐state reaction experiments. The SrO‐V2O5 boundary system contains 4 compounds at SrO to V2O5 molar ratios of 4:1, 3:1, 2:1, and 1:1. A fifth compound with a molar composition of ∼10:3 with the apatite crystal structure was also found; it may, however, be a hydroxyapatite phase. The CdO‐V2O5 system contains the compounds 3CdO·V2O5, 2CdO·V2O5, and CdO·V2O5. The latter compound exhibits a rapid reversible polymorphic transition at 180°C. Complete solid solubility exists in the SrO‐CdO system. The most probable compatibility relations were determined from the data available for the SrO‐CdO‐V2O5 ternary system. Limited solid solubility exists between SrO·V2O5 and CdO·V2O5, and the high‐temperature CdO·V2O5 polymorph is stabilized to room temperature by solid solution of SrO·V2O5. Evidence for the existence of 2 ternary compounds with limited local solid solubility is also presented.