Effects of dissolved oxygen on corrosion fatigue cracking of Alloy 690(TT) in pressurized water reactor environments

•This work was conducted in the simulated PWR environments under small scale yielding conditions.•The effect of DO level on corrosion fatigue cracking behavior of Alloy 690(TT) was observed.•The crack tip was characterized. Alloy 690(TT) is widely used for steam generator tubes in pressurized water reactor (PWRs), where it is susceptible to corrosion fatigue. In this study, the effects of dissolved oxygen on the corrosion fatigue cracking behavior of Alloy 690(TT) in simulated PWR environments were investigated under small scale yielding conditions. Dissolved oxygen, combined with the monotonic plastic zone size (rp), had a significant influence on out-of-plane cracking of corrosion fatigue crack and environment factor (Fen).