High temperature interaction of uranium and zirconium with water vapour

Physicochemical analysis of interaction of U, Zr and its alloy containing 1% Nb with the water vapour at temperatures up to 1500 K has been carried out. The kinetics and mechanism of the interaction of these metals with water vapour have been considered. It has been established that at temperatures up to 700 K the uranium oxidation variate linearly, and at temperatures above 900 K parabolically in time. When interpreting the uranium oxidation mechanism, structure defects and electrochemical properties of formed uranium oxides have been taken into consideration. Oxidation of Zr and its alloy with 1% Nb in water vapour changes cubically (over the range 900-1200 K) and parabolically (1300-1500 K) in time. Comparative analysis has shown that during uranium oxidation hydrogen emanation rate is approximately twice as high as this one for a vapour-zirconium reaction