In-Situ Characterization of High Performance Molten Salt and Material Interactions for Nuclear Applications

The Department of Energy is seeking the development of equipment to perform in situ interfacial characterization of interactions between molten salts and various materials for a fundamental understanding of interfacial behavior of materials in molten salt reactors. The company will develop an integrated cyclic voltammetry-Electrochemical Impedance Spectroscopy (EIS)-infrared spectroscopy approach to probe the corrosion of container material due to molten salts, under conditions of its intrinsic applied use in molten salt nuclear reactors. Overall, the proposed test unit will provide data that will improve molten salt nuclear reactor design, cost, performance, and safety by enabling the characterization interaction and identifying corrosion in alloys used for molten salt containment. This will also ultimately provide real time information from functioning molten salt nuclear reactors in order to predict and avoid corrosion failures in these complex molten salt containers. In Phase I, the company will show the effectiveness of cyclic voltammetry and EIS for characterizing interfacial reactions for complex molten salt – alloy systems and verify the results with synchrotron hard X-ray fluorescence and diffraction spectroscopy. This will support a Phase II cyclic voltammetry-EIS-infrared spectroscopy approach as an effective technique for in situ characterization of interfacial interactions between molten salt and materials and will lead to better approaches to imparting corrosion resistance. A cyclic voltammetry – EIS – molten salt laboratory setup will be constructed for testing. In Phase I, 316 stainless steel in typical molten salt will be used to manage costs during the early testing. In Phase II Inconel Alloy 617 will be used. An effective technique for in situ characterization of interfacial interactions between molten salt and materials will introduce better approaches to imparting corrosion resistance within and beyond the nuclear energy industry. This method of thoroughly characterizing the corrosive interaction between molten salts and alloy systems will improve the safety and performance of molten salt reactors enabling the nuclear energy industry to capitalize on molten salt reactors, thereby advancing nuclear energy generation. This technology will also be useful throughout industry, as corrosion is ubiquitous in metallurgy. Improved alloys will result in saving for manufacturing and infrastructure throughout the nation.