Skip to main content

Chemical Compatibility of Silicon Carbide In Molten Fluoride Salts for the Fluoride Salt-cooled High Temperature Reactor

Publication Type
Journal Name
Journal of Nuclear Materials
Publication Date
Page Numbers
119 to 134

Silicon carbide is widely appreciated for its high temperature strength, radiation tolerance and neutronic transparency in applications for fuel particles and core internals of nuclear reactors. However, in the Fluoride Salt-Cooled High Temperature Reactor, silicon carbide ceramic matrix composites will be exposed to harsh chemical and radiological environments. Silicon carbide is wettable and reacts electrochemically with dissolved metals. Metal impurities, tritium, moisture-based impurities and fission products in the coolant could accelerate hot corrosion of silicon carbide composites. The corrosion behavior of materials correlates with tritium production rates. Tritium can become trapped in radiation defects of silicon carbide. Thus, redox control and tritium recovery systems are necessary to mitigate silicon carbide corrosion in molten fluoride salt systems. Here, we survey current research on silicon carbide corrosion in molten fluoride salts and critically evaluate the research and development gaps.