A Combined Experimental and Computational Thermodynamic Investigation of the U–Th–O System. Issue 6 (21st March 2016)

• Record Type: Journal Article
• Authors: McMurray, Jacob Wesley; Voit, Stewart L.; Besmann, Theodore M.
• Editors: Jantzen, C.
• Is Part Of: Journal of the American Ceramic Society. Volume 99:Issue 6(2016)
• Page Start: 2197
• Page End: 2209
• Publication Date: 2016-03-21
• Subjects: Ceramics -- Periodicals; 620.1405
• DOI: 10.1111/jace.14180
• Languages: English
• ISSNs: 0002-7820

Abstract

Abstract : The thermodynamics of the U–Th–O system have been assessed using the Calphad method. The compound energy formalism (CEF) and a partially ionic two‐sublattice liquid model (TSLM) were used for the fluorite U1– y Th y O2± x, γ‐(U, Th)4 O9, and the U–Th–O melt. The O2 activity of fluorite U1– y Th y O2± x with temperature and composition was determined by thermogravimetric analysis. Thermodynamic studies for the Th–O binary and U–Th–O ternary available in the open literature were critically reviewed. A self‐consistent data set was selected and compiled with the equilibrium oxygen pressures determined by thermogravimetry in order to optimize the adjustable parameters of models selected to represent the phases in the Th–O and U–Th–O systems.