Effect of low dose irradiation of heavy ion on electrochemical corrosion and IASCC behavior of austenitic steel

Abstract The impacts of low dose irradiation on the behavior of electrochemical corrosion and irradiation assisted stress corrosion cracking for 321 stainless steel were studied using Fe 2+ ion irradiation to simulate neutron radiation damage in primary circuit environment of pressurized water reactor. Low dose irradiation can improve the pitting resistance and reduce the cracking tendency of the alloy in B-Li solution to a certain extent, which was related to the δ phase content on the near-surface of the sample: The higher δ phase content on the near-surface of the 2 dpa irradiated sample was observed by grazing incident X-ray diffraction. In addition, the pits was significantly increased near micro-cracks for the unirradiated sample, indicating that the existence of pits induced the initiation of cracks. The research results provided an important reference for the failure mechanism of irradiation assisted stress corrosion cracking of core components.