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I. Core application background: In water-cooled reactor systems, aluminum and its alloys are commonly used as structural materials in low- and medium-temperature water reactors. Anodizing treatment can significantly enhance their resistance to pitting corrosion; however, this process is only applicable in conditions where the water temperature does not exceed 100°C, as higher temperatures result in a significant reduction in the protective effect. II. Core Principle of the Process: This process is an electrochemical oxidation process in which the metal workpiece is used as the anode and placed in an electrolyte such as sulfuric acid. By applying direct current, an alumina protective film is formed on the surface of the metal; this film consists of a dense inner layer and a porous outer layer. The thickness of this film ranges from a few micrometers to several dozen micrometers, which significantly enhances the metal’s corrosion and wear resistance. III. Key process requirements: Solution control – Use an electrolyte of sulfuric acid at a concentration of 200–250 g/L, and strictly control the chloride ion content to prevent corrosion of the film layer. Parameter control: Under normal operating conditions, the temperature should be maintained between 18-22°C, the current density should be set at 1.2-1.8 A/dm², and the treatment time should range from 30 to 60 minutes. Sealing treatment: After oxidation is complete, the surface is sealed using deionized water at 90–110°C to fill the pores in the film layer, thereby further enhancing corrosion resistance. IV. Application precautions: In water-cooled reactors, the depth of local damage to aluminum materials should be kept within the safe range of 0.15 mm–0.30 mm, in order to prevent abnormal accelerated corrosion resulting from the destruction of the oxide layer and ensure the long-term stable operation of the system.