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Given the extreme operating conditions mentioned earlier, such as high temperatures, corrosion by highly fluorinated molten salts, and intense neutron irradiation, GH3535 (corresponding to the international grade Hastelloy N/UNS N10003) is currently recognized as the most suitable structural material for molten salt reactors. Key adaptation advantage: outstanding corrosion resistance. In an environment of molten fluoride salts at 704°C, the annual corrosion rate is only about 0.025 mm, which is less than 1/3 of the diameter of a human hair – far superior to that of traditional stainless steels and common corrosion-resistant alloys. A precise composition design of \"low chromium and high molybdenum\" is employed to fundamentally avoid the problem of selective dissolution and corrosion of chromium by fluoride molten salts. Its comprehensive properties meet the requirements: the tensile strength at 700°C is ≥650 MPa, and it possesses excellent high-temperature strength and creep resistance, enabling long-term stable operation in conditions ranging from 650 to 750°C. It exhibits excellent resistance to radiation damage, with a much lower degree of hardening after irradiation compared to ordinary alloys, making it suitable for the high-neutron irradiation environment inside reactors. Its proven maturity in practical application makes it the only structural material in the world that has been tested through decades of operation of molten salt reactors, and it has been certified in accordance with ASME nuclear-grade pressure vessel standards. Our country has achieved full domestic production of this alloy, supplying it in bulk for domestic thorium-based molten salt reactor projects, with core components accounting for over 95% of the total supply. Other materials such as C-276 Hastelloy and refractory high-entropy alloys either suffer from selective corrosion issues due to their high chromium content, or are still in the laboratory research phase; therefore they cannot yet replace GH3535 in its role as the primary suitable material.