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Considering the operating conditions of the various components in water-cooled reactors as mentioned earlier, there is no universal alloy that possesses the absolute best performance; the choice must be based on the specific application. The mainstream alloy that offers the best overall performance is Inconel 690 (a nickel-based alloy). Inconel 690 alloy is the key material used in current pressurized water reactor steam generators. Since its introduction in the 1990s, no instances of damage have been reported. Its resistance to intergranular corrosion and stress corrosion is far superior to that of Inconel 600 and 304 stainless steel; it can operate stably for long periods in acidic environments with a concentration of 98.5%, at high temperatures of 150°C. It is suitable for the operating conditions of high-temperature, high-pressure water-cooled reactors. Currently, this material has been manufactured domestically in China. As a nickel-iron-chromium-based alloy developed independently in China, the new domestic alloy No. 13 boasts pitting and stress corrosion resistance comparable to that of Inconel 690. It exhibits excellent stability in high-temperature water containing NaOH, and its tendency to harden upon cold working is lower than that of 1Cr18Ni9Ti stainless steel; thus, it represents a cost-effective domestic alternative material suitable for use in pressurized water reactor evaporators. Alloys suitable for special applications: In the case of fuel cladding, zirconium alloys (such as the domestically produced N36) are the optimal choice for core cladding in water-cooled reactors, owing to their extremely low thermal neutron absorption cross-section; their corrosion resistance makes them suitable for use in high-temperature water environments ranging from 300 to 400°C. Supercritical water-cooled reactor scenario: The high-temperature strength and corrosion resistance of Incoloy-800H alloy make it more suitable for supercritical operating conditions above 374°C.