On the kinetics of UO2 interaction with molten Zircaloy at high temperatures

The theoretical study of kinetic processes of UO2/Zr reaction at high temperatures is presented. Possible reasons for the plane interphase boundaries destruction are suggested for two temperature ranges studied experimentally, 1200-1700deg C (solid Zr) and 1900-2200deg C (liquid Zr). On the basis of the proposed mechanisms of moving boundaries instability, two different approaches are presented to describe mass transfer through the two-phase region, that appears as a result of interphase boundary instability. (orig.)