|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Advanced Characterization and Modeling of Nuclear Fuels: Microstructure, Thermo-physical Properties
||Thermal Energy Transport in Defect-bearing and Uranium-doped Single Crystal Thorium Dioxide
||Cody A. Dennett, David Hurley
|On-Site Speaker (Planned)
||Cody A. Dennett
Actinide fluorite oxides form an important class of nuclear fuel materials. Thorium dioxide is of particular interest as a fuel candidate due to its extremely high melting point and fixed tetravalent cation oxidation state. Potential operating environments, however, include high radiation fields which directly generate lattice defects or require uranium doping for fuel utilization. Defects and doping drastically influence thermal transport, a controlling safety and performance property. Little experimentally-validated understanding has been generated on the role of defect formation and doping chemistry on thermal transport due to the lack high-quality starting material. Here, single crystals of pure thoria are exposed to proton irradiation to generate defects, while a subset are grown with low uranium doping (maximum 16at%). The mesoscale thermal conductivity of damaged and doped crystals is measured using a spatial thermoreflectance technique. Experimental values are compared with calculated conductivity from thermal transport models, considering the relevant phonon scattering mechanisms.