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The effect of radiation on the corrosivity of liquid metal coolants is generally minor; it does not significantly increase corrosion under normal reactor operating conditions. This can be divided into two scenarios: when corrosion is controlled by solute diffusion, the liquid metal itself is a monatomic substance with good radiation stability, and the structural defects induced by radiation can be ignored. Such defects have almost no impact on the diffusion coefficients within the liquid metal, so they do not alter the corrosion rate. When corrosion is controlled by the solid dissolution process, if the reaction involves multiatomic substances (such as iron corroding in sodium to form FeO·2Na₂O), or if there is a viscous protective film on the solid surface, the bombardment by radiation particles may cause the removal of this film layer, which theoretically could lead to accelerated corrosion. A large number of in-core tests have shown that, within the irradiation flux ranges of current power reactors and space reactors, no significant increase in the corrosion of liquid metals due to irradiation has been observed. The corrosion behavior of structural materials such as stainless steel and iron-based alloys in liquid metals like sodium and lead-bismuth remains essentially unchanged before and after irradiation, as indicated by their mechanical properties and metallographic analysis results