Fatigue Behavior of Cold-Worked 304 Stainless Steels under In-Situ Irradiation at 300°C

Abstract

Stress-controlled fatigue tests were performed for 5% and 15% cold-worked 304 stainless steels under in-situ irradiation with 17 MeV protons at 300°C. Increase of fatigue life with prolonged crack propagation length under in-situ irradiation was detected for 5% cold-worked specimens, whereas no significant difference was observed in fatigue life or crack propagation length between in-situ irradiation and unirradiated conditions for 15% cold-worked specimens. Fractographic analysis of the fatigue fracture surface suggested more significant participation of strain-induced martensite in fatigue behavior for 15% cold-worked specimens. The strain-induced martensite in 15% cold-worked specimens would play an important role in reducing the in-situ irradiation effect on fatigue behavior based on the interaction between radiation-induced defect clusters and moving dislocations.