STRESS CORROSION CRACKING IN A STAINLESS STEEL 308L-316L WELD JOINT IN PRIMARY WATER

摘要

Stress corrosion cracking (SCC) in a stainless steel 308L-316L weld joint in primary water was investigated with a focus on the behavior of SCC propagation to the fusion boundary (FB) in the heat affected zone (HAZ). Stress corrosion crack growth in the HAZ was observed in an off-normal water chemistry condition with dissolved oxygen (DO), but not in a normal water chemistry condition with dissolved hydrogen. This suggests that it is unlikely the SCC could reach the FB and penetrate into the weld metal in the primary water with normal chemistry condition. Microstructure analysis of the crack tip suggests that the SCC in the HAZ in primary water with DO follows the slip-oxidation mechanism.