Recently, the Consortium for Advanced Simulation of LWRs (CASL) Energy Innovation Hub was entered a second 5-year phase. During the first 5 years, the Fuels, Materials and Chemistry (FMC) technical focus area within the CASL program focused on addressing materials science aspects of three challenge problems: (1) pellet-cladding interaction (PCI) fuel failures, grid-to-rod fretting (GTRF) fuel failures and impact of CRUD on reactor operation (as well as enchanted corrosion). For these challenge problems, FMC delivers engineering scale fuel performance models and materials physics-based constitutive and behavioral models. Highlights in these areas from the first 5 years of the program will be presented, including comparison to operational nuclear power plant data. In addition, plans for the second phase of CASL will be discussed. In particular, emphasis will be placed on the development of advanced models of the fuel and cladding behavior during accident conditions (RIA and LOCA).