Effects of silicon carbide on the corrosion of metallic materials in molten LiF-NaF-KF salt

The effects of silicon carbide (SiC) on the corrosion behavior of metallic materials in molten LiF-NaF-KF (FLiNaK) salt were investigated. Results reveal that the corrosion products of SiC in molten FLiNaK salt can react with nickel-based alloy GH3535, Ni metal, 316L stainless steel, and Cr metal to form Ni31Si12, Ni3Si, CrFe8Si, and Cr3Si, respectively. The formation of silicide enhances the corrosion of GH3535 alloy in molten FLiNaK salt. The depletion of Cr along grain boundaries in alloys can promote the diffusion of silicon into the alloys and increase the corrosion depth.