Thermochemical and Thermophysical Properties of Advanced Fission Fuel Materials

Abstract

Burning or transmutation of minor actinides (MA: Np, Am, Cm) as well as plutonium is an option for the future nuclear fuel cycle. For the transmutation of MA, research and development of MA-bearing fuels that are quite different from the current UO2 and (U,Pu)O2 fuels have to be made. Among various fuel types, nitride is one of the attractive fuels to the MA-bearing fuel. The thermochemical and thermophysical properties of nitride fuels available in literature, such as the thermal expansion, specific heat capacity, thermal conductivity, thermal creep, vaporization behavior, etc., are briefly reviewed and the new data obtained on actinide nitrides are presented. The thermal expansion was measured by high-temperature X-ray diffraction, the thermal diffusivity by laser-flash method, the thermal creep by compression method, Young’s modulus by pulse echo method, and the hardness by indentation method.