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Building on the previous understanding of the basic effects of ionizing radiation on cathodic processes, its long-term action leads to multi-dimensional, ongoing evolutionary effects: the decomposition products of the medium continue to accumulate. Under prolonged irradiation, decomposition products such as hydrogen peroxide and oxidizing groups in substances like water keep accumulating, acting as depolarizers that accelerate cathodic reactions; these products do not disappear completely once the irradiation stops, thereby maintaining a highly active state for the cathodic process. The performance of the oxide film on metal surfaces deteriorates. Prolonged exposure to radiation continuously damages the lattice structure of the oxide film on the metal surface, increasing the electrical conductivity of the film. This allows the cathodic reactions to spread from local pores throughout the entire film surface, thereby significantly extending the accelerated aging time of the cathodic process. The long-term evolution of microdefects: The point defects introduced by irradiation migrate and aggregate over time, forming stable microstructures such as dislocation loops and voids. This continues to alter the electrochemical activity of the metal surface, resulting in a prolonged acceleration effect of the cathodic process that prevents it from returning completely to its unirradiated state. Irreversible degradation of material properties: Under long-term exposure, metals undergo irreversible changes such as irradiation hardening and helium embrittlement, which further alter the interface conditions of the cathodic reactions. This ultimately leads to a sustained decline in the material’s corrosion resistance and significantly shortens the service life of the components.