Influence of Severe Plastic Deformation on the Stress Corrosion Behavior of Type 316 Stainless Steel

Type 316 stainless steel (SS316) is widely used in marine, chemical, and structural environments due to its excellent corrosion resistance; however, its susceptibility to stress corrosion cracking (SCC) in chloride-containing conditions remains a limitation for long term reliability. This work investigates the influence of severe plastic deformation (SPD) via Equal Channel Angular Pressing (ECAP) and High-Pressure Torsion (HPT), which creates ultrafine-grained and nanocrystalline microstructures respectively, on the SCC behavior of SS316. The SCC susceptibility was evaluated using slow strain rate tensile testing (SSRT) at 10^-6 s^-1 in both air and 3.5 wt.% NaCl solution at room temperature. Comparative study with as-received coarse-grained SS316 was performed under similar conditions. The SCC susceptibility index decreased for SPD SS316 compared to CG SS316. This result demonstrates that SPD significantly reduces the SCC susceptibility of SS316.