Study on irradiation induced corrosion behavior in austenitic stainless steel using hydrogen-ion bombardment

In order to study the basic factors in irradiation assisted stress corrosion cracking (IASCC) of austenitic steels, the effects of displacement damage on the corrosion behavior of type 304 stainless steel were investigated by means of an ion irradiation technique. Solution-annealed specimens was irradiated using 1 MeV protons to 0.1, 0.5 and 1.0 dpa at about 573, 673 and 773 K. Electrochemical potentiokinetic reactivation (EPR) testing was carried out before and after the ion irradiation to clarify the effects of irradiation on corrosion behavior. The specimens irradiated at 773 K showed clear etching at grain boundaries and relatively high reactivation ratio, however, the specimens irradiated at 573 and 673 K showed no clear grain boundary etching. It was suggested that the higher irradiation temperature enhanced the radiation induced segregation near grain boundaries.