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I. Typical corrosion characteristics of different types of special reactors: Molten salt reactors: Molten fluoride salts at 600°C can cause temperature-driven mass transfer corrosion; the specific atomic arrangement in some alloys creates \"corrosion fast tracks\", accelerating material degradation. Lead-bismuth fast cooling reactors: In addition to the dissolution and corrosion caused by high-temperature liquid lead-bismuth, there is also a problem of liquid metal embrittlement at around 350°C, which significantly reduces the material’s elongation rate and fatigue life. Special systems in water-cooled reactors: Flow-accelerated corrosion, pitting, crevice corrosion, and stress corrosion cracking occur in the secondary side return lines, while the heat transfer tubes of the steam generator are areas prone to failure. Gas-cooled reactors: At high temperatures, carbon dioxide can cause reactions in graphite and carburization of stainless steel; impurities in helium can also lead to oxidation and peeling of components. II. Core protection technologies: Selection of corrosion-resistant materials – Nickel-based alloys such as Hastelloy C-276 are used to resist corrosion by molten salts, while the composition of ferritic/martensitic steels is modified to withstand corrosion caused by high-temperature lead and bismuth; industrial-scale production of materials resistant to lead and bismuth corrosion has already been achieved in China. Coating protection: Thermal barrier coatings and self-healing ceramic coatings are used to form a dense protective layer on the metal surface, thereby reducing the likelihood of the substrate coming into contact with corrosive agents. Environmental control: Optimizing the quality of the coolant, controlling the impurity content in molten salts, and improving the corrosion resistance of materials in a liquid metal environment by adjusting oxygen concentration. Electrochemical protection: In seawater-related systems, the sacrificial anode method and impressed current cathodic protection systems are employed, with the protection current being adjusted dynamically to suppress corrosion. Cutting-edge monitoring technologies: Institutions such as MIT have discovered that certain irradiation conditions can reduce the corrosion rate of certain alloys, while three-dimensional X-ray monitoring techniques enable real-time observation of the corrosion and cracking processes in materials, thereby supporting the development of new materials.