Effect of Heat Treatment on Thermal Conductivity of U-Mo/Al Alloy Dispersion Fuel

Abstract

The molybdenum content of fuel core whose matrix is aluminium 1060, was varied to be 7, 8, and 10 wt% and the volume fraction of U-Mo fuel powders was varied to be 10, 30, and 40 vol%. In this work, thermal conductivities were calculated from measured thermal diffusivities, specific heat capacities, and densities, which were determined using the laser flash, DSC, and Archimedes methods, respectively. The thermophysical properties were measured over a temperature range from room temperature to 500°C. The U-Mo alloy was annealed at between 525 and 550°C for 1 to 36 hours. At high temperature, the U-Mo particles were reacted with aluminium matrix as forming layers of (U-Mo)Al _x . These reaction layers have been affected adversely by the thermal conductivity of fuel core. The thermal conductivities of annealed samples appeared to decrease with increasing volume fraction of the reaction layers.