Stress corrosion crack initiation susceptibility of laser powder bed fused and powder metallurgy-hot isostatic pressed type 316L stainless steels in high-temperature water environments

• SCC initiation susceptibility in three light water reactor environments was evaluated • LPBF-HIP and PM-HIP 316L have lower SCC susceptibility than wrought 316L • Reduced grain size, nano oxides and the non-recrystallized grains retard SCC Laser based powder bed fusion (LPBF) and powder metallurgy via hot isostatic pressing (PM-HIP) are advanced manufacturing technologies for nuclear components. In the present study, stress corrosion crack (SCC) initiation susceptibility of LPBF 316L stainless steel post-treated by HIP, PM-HIP 316L and also wrought 316L specimens were evaluated in three typical light water reactor environments by U-bend testing and post-exposure characterizations. Results show that LPBF-HIP and PM-HIP 316L have lower SCC susceptibility compared to their wrought counterparts in the selected environments tested. The mechanisms for SCC behavior of samples were discussed.