Pit to crack transition behavior in proportional and non-proportional multiaxial corrosion fatigue of 304 stainless steel

Multiaxial corrosion fatigue tests with interruption were carried out on 304 stainless steel in 6 wt.% FeCl3 solution at room temperature. Pit initiation, growth and pit to crack transition behavior under proportional and non-proportional loading were investigated. Under proportional loading, significant sharper pits, higher initial pit density and growth rate were observed in comparison with non-proportional loading. The pit depth growth rate under proportional loading was larger than those under non-proportional loading and without loading. Pit to crack transition mechanism was mainly controlled by mechanical assisted local dissolution under proportional loading while additional hardening under non-proportional loading.