Towards in-Situ Corrosion Measurements in Molten Fluoride Salt By Simultaneous X-Ray Absorption Spectroscopy and Electrochemistry

Effects of corrosion products on molten salt properties are a focus of many studies motivated by the needs of molten-salt nuclear reactors. We demonstrate in-situ measurements of corrosion products from NiCr (80%-20%) foil in molten FLiNaK. We used X-ray absorption spectroscopy (XAS) and a combination of XAS with electrochemical spectroscopy. Using XAS, we measured both the space and time distributions of Ni and Cr ions leaching from the foil and characterized their valence state and the local structure. We also correlated the XAS results with simultaneous electrochemical measurements. We also demonstrated a novel sample environment that we developed that enables simultaneous XAS and electrochemical measurements of molten fluoride salts. The next step of this program is to measure the corrosion on structural alloys such as stainless steel in molten FLiBe.