Experimental investigation of stress effect on swelling and microstructure of Fe–16Cr–15Ni–3Mo–Nb austenitic stainless steel under low-temperature irradiation up to high damage dose in the BOR-60 reactor

The present paper was devoted to investigation of the stress effect on swelling and microstructure evolution of the Fe–15.8Cr–15.3Ni–2.8Mo–0.6Nb steel irradiated in the BOR-60 reactor at temperatures from 395 to 410 °C and damage doses from 79 to 98 dpa. Was found out that the stress increase leads to an increase of swelling, that can be associated with a decrease in incubation period with a practically constant swelling rate. Voids concentration increases at the first stage of irradiation when the void sizes are practically constant, and then the concentration reaches some saturation and swelling increase is caused by void growth.