Environmentally assisted crack growth in 308L stainless steel weld metal in simulated primary water

Environmentally assisted crack growth behavior of 308L stainless steel weld metal in simulated primary water was investigated. The results showed ultra-low stress corrosion crack growth in the weld metal. However, obvious environmental acceleration of fatigue crack growth was observed, which is increased by more aggressive water chemistry and gentle cyclic loading conditions. Further, the environmental fatigue crack growth rate of 308L weld metal was lower than that of 304 and 316 stainless steels under the same environmental and loading conditions. This was attributed to the retardation of crack growth by δ ferrite phase.