Corrosion Resistant Cold Sprayed Cladding for Molten Salt Reactors

Abstract

The bimetallic structure concept consisting of a corrosion resistant surface layer joined on top of an ASME code-approved substrate becomes a promising solution to address the corrosion issue of ASME substrate materials in molten salt environment. Specifically, refractory materials such as molybdenum, tungsten, and alloys containing them are found to be most resistant in molten salt environment and hence they have great potential to be used as the protective salt-facing surface layer. Due to the well-recognized difficulties of welding/3D-printing refractory materials (i.e., oxidation, brittle phase formation, cracking, etc.), cold spray, a deposition technology that minimizes material heating, avoids undesired thermal effects and maintains dimension stability, is an ideal approach for fabricating the bimetallic components. A corrosion resistant cladding material that is also amenable to cold spray process is desired and has been developed. Promising cladding structure has been designed, and tested by both molten salt corrosion and cold spray trials for down-selection. Prototyping for clad adhesion test will also be conducted as proof-of-concept validation. This program is sponsored by DOE Office of Nuclear Energy.