Material Issues for the Application of SiC Composites to LWR Fuel Cladding

Silicon carbide (SiC)-based ceramics and their composites (SiCf/SiC) have extensively been studied for fusion and advanced fission energy systems due to the excellent high temperature properties, irradiation tolerance, inherent low activation and other superior physical/chemical properties. In the high temperature gas-cooled reactors (HTGRs), SiC is being utilized as a coating layer of TRISO particle fuel and SiCf/SiC composites can also be applied to in-/out of core structural materials including control rod sheath and intermediate/process heat exchanger components. In addition, SiCf/SiC composites have been considered as blanket structural materials and flow channel insert in fusion reactors. Recently, there have also been efforts for applying the SiCf/SiC composites to light water reactor (LWR) fuel cladding. However, there are a lot of technical issues need to be clarified for the LWR application because the previous research on the SiCf/SiC composite has mostly been focused on the high-temperature application. In this study, we reviewed material issues regarding to the application of SiC composite to LWR fuel cladding. We tried to draw a research direction and important issues to assess the technical feasibility of SiC composite cladding