2017 | AFC ACCOMPLISHMENTS 88 Dual-Purpose Coating Development for SiC-Based LWR Cladding Principal Investigator: Dr.Yutai Katoh (ORNL) Collaborators: Dr. Caen Ang (ORNL), Dr. Stephen Raiman (ORNL), Dr. Xunxiang Hu (ORNL), Dr. Kurt Terrani (ORNL) Silicon carbide (SiC) continuous fiber-reinforced SiC matrix composite (SiC/SiC composite)- based fuel cladding is a concept that potentially enables an Light Water Reactor (LWR) core with ultimate accident-tolerance. For this concept to demonstrate the technical feasi- bility, chemical compatibility with the radiolytic water and containment of gaseous fission products are the two leading issues. Coating with a material that provides the corrosion barrier and the hermetic sealing is among the promising approaches to address these critical challenges. Technology development for this dual-purpose coating was concep- tualized and pursued by a team of Oak Ridge National Laboratory researchers. Project Description: As the potential accident-tolerant fuel cladding material, SiC/SiC composites are known to combine Figure 1. Cr multilayer coatings on SiC substrates deposited by physical vapor deposition process. RP and TM represent vendors that collaborated with the program.