Effects of Rolling Speed and Reduction on Rolling Simulation Results of Monolithic Fuel Plates

Abstract

Abstract The in-pile performances of UMo/Zr monolithic nuclear fuel plates are directly related to their manufacturing quality. The interface bonding strength depends on the contact pressures over the surfaces of the Zircaloy covers, the Zircaloy frame and the UMo coupon during rolling. The contact pressures are affected by the process parameters such as the rolling speed and the reduction per pass. These parameters should be carefully investigated to optimize the fabrication process. In this study, a three-dimensional stress updating algorithm is presented for the strain-rate-dependent mechanical constitutive relation of Zircaloy. Three-dimensional FEM simulation of the rolling process for monolithic nuclear fuel plates is carried out. The influences of the rolling speed and reduction on the geometrical shape and the contact pressure between the Zircaloy cover and the coupon will be discussed according to the computational results. The results indicate that (1) along the plate width direction the maximum contact pressure between the coupon and the Zircaloy cover exists at the center and decreases towards the edge; (2) when the rolling speed or reduction increases, the maximum contact pressure increases as well; and the dog-bone shape of the coupon at the back end is more visible.