Effect of concentration of Cr3+ in LiF-NaF-KF salt on the corrosion of SiC

Effect of the concentration of Cr3+ in molten LiF-NaF-KF salt on the corrosion of SiC was investigated. Results reveal that increasing initial concentrations of Cr3+ in salt can enhance both the loss of Si and the deposition of Cr on SiC, which results in the weight change of SiC from loss to gain. The corrosion of SiC in molten LiF-NaF-KF salt with Cr3+ should be attributed to the oxides in SiC, the oxygen-containing impurities and Cr3+ in salt. The oxygen-containing impurities in salt react with SiC to form oxides that can be corroded by fluoride salt. The Cr3+ in salt can react with SiC and the oxides (SiOx).