Corrosion behavior of ion-irradiated SiC in FLiNaK molten salt

Abstract

High-purity 4H-SiC samples exposed to 1-MeV Si ions irradiation at RT were corroded in FLiNaK molten salt at 650° C for 168 h. Results revealed the corrosion degree of irradiated SiC was dependent on the irradiation fluence. The amorphous region induced by irradiation was preferentially corroded, where Si elements could dissolve into the salt more easily than those in the unirradiated region. The dissolution of Si elements caused the formation of sustained nanocracks and nanopores, and thus the corrosion layer having a thickness of 200 ± 50 nm fell off. Moreover, oxygen impurities might play a role in the irradiation-assisted corrosion.