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The highly corrosive high-temperature environment of fluoride molten salts imposes strict requirements on material properties. The corrosion-resistant materials that have been proven effective can be classified into the following categories: First, nickel-based alloys such as Hastelloy N (NS3304): This is the only material in the world that has been tested in engineering applications over several decades; in a 704°C environment with molten fluorides, its annual corrosion rate is less than 0.025 millimeters. It has obtained ASME certification for nuclear-grade pressure vessels, making it the most mature option for industrial use. Inconel 600/617, Hastelloy N: exhibit significantly superior corrosion resistance in 700°C FLiNaK molten salts compared to ordinary stainless steels, with lower corrosion rates and higher polarization impedance. II. Refractory high-entropy alloys such as NbTaMoW and NbTaMoWV: These are refractory high-entropy alloys with a body-centered cubic structure; they possess excellent thermal stability and mechanical strength at high temperatures. They also show good corrosion resistance in FLiBe molten salts, making them candidate materials for next-generation molten salt reactors. III. Carbide ceramics – MoC: In FLiNaK molten salt at 850°C, its corrosion rate is merely 0.26 μm/100h; it is the carbide ceramic with the best corrosion resistance. SiC, ZrC-SiC composites: SiC itself has excellent corrosion resistance, and as the proportion of SiC in the composite increases, the overall resistance to fluoride salt corrosion also improves, allowing them to be used in extreme high-temperature environments above 850°C. IV. Graphite types: Nuclear-grade graphite presents no issue whatsoever with resistance to corrosion by high-temperature fluorides; it is the preferred material for moderators in molten salt reactors. Its use as a pressure-bearing structural component is limited only by its insufficient mechanical strength.