Experimental oxygen potentials for U1−yPryO2±x and thermodynamic assessment of the U-Pr-O system

Abstract Thermogravimetric analysis (TGA) was used to determine the oxygen potentials of fluorite urania-praseodymia (U1−yPryO2±x) solid solutions for y = 0.10 and 0.20 between 1000 and 1500 °C. A thermodynamic assessment of U-Pr-O system was performed using the CALPHAD (CALculation of PHAse Diagrams) method. The models well reproduce the TGA measurements and the computed phase relations are in good agreement with those proposed from an X-ray diffraction investigation.