OXIDATION STUDIES ON U-ZR ALLOYS

Oxidation of U-Zr alloys (10 to 90 at% Zr) in air was studied thermogr avimetrically under isothermal as well as nonisothermal modes of heati ng. Increase in zirconium concentration led to decrease in reactivity with air. Based on the chemical analyses of the intermediate products, there appears to be a slight preferential oxidation of uranium in the matrix during the initial stages of the oxidation. The analysis of th e intermediates by XRD indicated the formation of solid solution of UO 2 and ZrO2. Kinetic parameters were evaluated for the oxidation reacti ons and the mechanism of the process is suggested.