Stress corrosion cracking of 316L HAZ for 316L stainless steel/Inconel 52M dissimilar metal weld joint in simulated primary water

The stress corrosion cracking (SCC) behaviour of 316L heat affected zones (HAZ) in 316L stainless steel/Inconel 52M dissimilar metal welded joint (DMWJ) in simulated primary water was systematically evaluated using direct current potential drop (DCPD) methods. Crack growth rates (CGRs) of 316L HAZ increased with increasing temperature and dissolved oxygen (DO) contents. CGR in hydrogenated water was approximately one order of magnitude slower than in oxygenated water. The fracture surface shows typical mixed intergranular-transgranular SCC characteristics and several fast finger-like cracks. Several intergranular secondary cracks, perpendicular to the main crack and fusion boundary, were also observed.