Corrosion Behavior of Inconel Alloys in a Hot Lithium Molten Salt under an Oxidizing Atmosphere

The electrolytic reduction of spent oxide fuel involves the liberation of oxygen in a molten LiCl electrolyte, which results in 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 handling molten salt. In this study, corrosion behavior of Inconel 713LC, MA 754, X-750 and 718 in the molten salt LiCl-Li2O under an oxidizing atmosphere was investigated at 650 degrees C for 72216 hours. Inconel 713LC alloy showed the highest corrosion resistance arming the examined alloys. Corrosion products of Inconel 713LC were Cr2O3, NiCr2O4 and NiO, and those of Inconel MA 754 were Cr2O3 and Li2Ni3O10, while Cr2O3, NiFe2O4 and CrNbO4 were produced from Inconel 718. Also, corrosion products of Inconel X-750 were found to be Cr2O3, NiFe2O4 and (Cr,Nb,Ti)O-2. Inconel 713LC showed local corrosion behavior and Inconel MA 754, 718, X-750 showed uniform corrosion behavior.