Intergranular Stress Corrosion Cracking growth perpendicular to fatigue pre-cracks in T-L oriented compact tension specimens in simulated Pressurized Water Reactor primary water

Intergranular Stress Corrosion Cracking (IGSCC) growth observed perpendicular to the plane of fatigue pre-cracks in T-L oriented compact tension specimens made of highly cold-rolled Type 316 stainless steel has been investigated metallurgically. One-directional cold rolling resulted in significant lamellar local strains on the plane parallel to the rolling plane. Oxide was detected along intergranular crack. It is deduced that intergranular cracking was due to selective oxidation and enhanced high diffusivity at grain boundaries coupled with lamellar local strains. It is argued that strain-induced oxidation could be a possible mechanism for IGSCC in cold-rolled stainless steels in simulated Pressurized Water Reactor environment.