Room temperature and high temperature micromechanical testing of SiC- SiC fiber composites for nuclear fuel cladding applications

Silicon carbide ceramics are a candidate material for the use in nuclear power generation and are suggested to be used in novel accident tolerant fuel (ATF) cladding designs due to its favorable properties, in particular reduced (compared to Zircaloy) oxidation under accident conditions, good neutronic performance, high temperature strength and stability under irradiation. Due to its inherent brittleness, it is suggested to be used in the form of SiC-fiber reinforced SiC-matrix composite. In order to reliably model behavior of highly non-uniform and anisotropic composite materials the knowledge of the individual properties of fiber and matrix, and, crucially, the fiber-matrix interfaces, is required. In addition, nuclear fuel cladding materials are exposed to elevated temperatures during their operation, and therefore the understanding of the temperature dependences of the relevant properties is essential. Micromechanical testing techniques, such as nanoindentation and microcantilever beam fracture, allow determination of such localized properties, and can be implemented in the wide range of temperatures. Please click Additional Files below to see the full abstract