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The effect of ionizing radiation on the corrosion resistance of metals does not have a single consistent outcome; it varies depending on factors such as the type of radiation, dose, and metal material. This can be divided into two categories: First, in most cases, corrosion resistance is reduced as microscopic defects accelerate corrosion. High-energy particle irradiation induces various structural damages within the metal, such as point defects, dislocation loops, and helium bubbles, which provide pathways for the migration of ions from corrosive agents, thereby accelerating the corrosion process. For example, after zirconium alloy is irradiated with Ar⁺, the diffusion rates of O²⁻ ions and other corrosive agents increase, leading to a faster corrosion rate. Elemental segregation destroys the passivation film: Irradiation causes corrosion-resistant elements such as Cr and Ni to redistribute at the metal grain boundaries, resulting in localized chromium deficiency and the destruction of the dense passivation film on the surface of materials like stainless steel, thereby greatly increasing susceptibility to pitting and intergranular corrosion. Synergistic acceleration in special environments: In irradiated environments such as reactors and high-temperature molten salts, radiation also promotes the absorption and penetration of hydrogen, creating a synergistic effect with corrosion that further exacerbates metal corrosion fatigue damage. II. Improving corrosion resistance under specific processes: When 316L stainless steel is subjected to surface irradiation using a high-current pulsed ion beam (HIPIB), the surface can be smoothed, impurity elements can be selectively ablated, the structure of the surface layer can be optimized, the self-corrosion current can be significantly reduced, and the material’s resistance to electrochemical corrosion in corrosive media such as sulfuric acid can be enhanced.