Effect of irradiation on corrosion of 304 nuclear grade stainless steel in simulated PWR primary water

•Studied corrosion of proton-irradiated 304 stainless steel in high temperature water.•A higher irradiation dose results in formation of more and larger dislocation loops.•Irradiation promotes both the overall and intergranular (IG) corrosion of the steel.•Irradiation induced Cr depletion at grain boundary causes the promoted IG corrosion. Effect of irradiation on corrosion of 304 nuclear grade stainless steel (304NG SS) in simulated primary water of pressurized water reactor was investigated. The investigation was conducted by comparing the microstructure of the oxide scale formed on the steel irradiated to different doses by proton. The results revealed that increasing irradiation dose promoted both the corrosion and intergranular corrosion of 304NG SS. This is attributed to the irradiation induced defects as well as the Cr depletion at the grain boundary in the steel.