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Considering the background of synergistic degradation due to nuclear irradiation-induced creep and metal corrosion discussed earlier, its core mechanism can be divided into 3 interrelated stages: Irradiation first induces dual types of microscopic damage. High-energy particle irradiation creates numerous point defects such as vacancies and interstitial atoms within the metal; these defects promote dislocation climb through the \"stress-induced preferential absorption\" effect, thereby triggering irradiation creep； It also destroys the original lattice integrity of the metal and weakens the density of the surface passivation film. Creep and corrosion create a positive feedback loop: the continuous micro-deformations caused by radiation creep continually tear apart the protective oxide layer on the surface, exposing the fresh metal matrix directly to the corrosive environment ； The local thinning of the material caused by corrosion, in turn, increases the local stress levels, further accelerating the creep process. The combined effects of multiple mechanisms amplify the destructive impact. Radiation-induced degradation of the medium (resulting in the formation of oxidizing substances such as O₂ and H₂O₂), along with an increase in the electrochemical activity of metal surfaces, combine with these microscopic processes, ultimately increasing the overall corrosion rate of the metal by 1.2 to 4.4 times and significantly raising the risk of intergranular corrosion and stress corrosion cracking.