Hot corrosion behavior of Ni-base alloys in a molten salt under an oxidizing atmosphere

Abstract The electrolytic reduction of a spent oxide fuel involves liberation of the oxygen in a molten LiCl electrolyte, which is a chemically aggressive environment that is too corrosive for typical structural materials. So, it is essential to choose the optimum material for the process equipment for handling a molten salt. In this study, corrosion behaviors of Inconel 713LC, Inconel MA 754, Haynes 214 and Haynes HR-160 in a molten LiCl–Li 2 O salt under an oxidizing atmosphere were investigated at 650 °C for 72–216 h. Inconel 713LC alloy showed the highest corrosion resistance among the examined alloys. Corrosion products of Inconel 713LC were Cr 2 O 3 , NiCr 2 O 4 and NiO, and those of Inconel MA 754 were Cr 2 O 3 and Li 2 Ni 8 O 10 while Cr 2 O 3 , LiNiO 2 , (Al,Cr) 2 O 3 and LiFeO 2 were identified as the corrosion products of Haynes 214. Haynes HR-160 showed LiCoO2, CoCr 2 O 4 Li(Ni,Co)O 2 and (Cr,Ti) 2 O 3 as its corrosion products. Inconel 713LC showed a localized corrosion behavior while Inconel MA 754 and Haynes 214 showed a uniform corrosion behavior. In the case of Haynes HR-160, an intergranular corrosion was observed.