HISCC behavior of SUS301L-MT stainless steel laser-arc hybrid welding joints.

The hydrogen-induced stress corrosion cracking (HISCC) behavior of SUS301L-MT stainless steel laser-arc hybrid welding (LAHW) joints was investigated using slow strain rate tensile (SSRT) method in 3.5 wt.% NaCl solution under different cathodic potentials. With the negative shift of applied potentials from open circle potential (OCP) to −1400 mV SCE , the HISCC susceptibility index ( I SSRT ) decreased from 0.15 (OCP) to 0.06 (−400 mV SCE ), then increased to 0.28 (−1400 mV SCE ). The specimens tested in air and under OCP to −800 mV ruptured in weld metal zone with ductile features of dimples. While with the potential turned more negative, the specimens ruptured in base metal zone with brittle features of transgranular cleave in martensite, intergranular failure and secondary cracks [Chen et al., Int. J. Adv. Manuf. Technol.73, 1695 (2014)]. [ABSTRACT FROM AUTHOR]