Microstructural features of SIMFUEL - Simulated high-burnup UO(2)-based nuclear fuel
Simulated high-burnup nuclear fuel (SIMFUEL) replicates the chemical state and microstructure of irradiated fuel so that detailed experiments on fission-gas release, thermal conductivity and leaching can be undertaken in the laboratory. Eleven stable elements were added to simulate the compositions of 3 and 6 at% burnup UO(2)-based fuel. The preparation route featured high energy grinding and spray drying to achieve homogeneous dispersion of the feed materials on a submicrometre scale. Sintering at 1650 C then provided atom-scale mixing and second-phase development characteristics of high temperature fuels. The gases and volatiles cannot be introduced during fabrication, but can be added subsequently by ion implantation. The microstructure of SIMFUEL is found to be similar to that of irradiated fuel (without bubbles). Spherical metallic Mo-Ru-Pd-Rh precipitates are found uniformly dispersed throughout the matrix. A finely precipitated perovskite phase is observed, decorating the matrix grain boundaries.
Bibliographic Reference: Article: Journal of Nuclear Materials, Vol. 178 (1991) pp. 48-60
Record Number: 199111483 / Last updated on: 1994-12-02
Original language: en
Available languages: en