The effects of cold rolling and sensitisation on hydrogen embrittlement of AISI 304L welds

The notched tensile strength (NTS) of 304L stainless steel welds subjected to cold rolling (20% thickness reduction) and sensitisation treatment (600 °C/10 h) was measured in a MgCl₂ (40 wt.%) solution at 80 °C. The NTS loss, which is used for comparing the susceptibility to hydrogen embrittlement (HE), was consistent with the extent of embrittled area on the fracture surface of various welds. The HE susceptibility of the weld decreased after cold working but increased with the additional sensitisation treatment of the cold-rolled welds. Besides, cracks tended to propagate along the skeletal boundaries for all welds tested in the MgCl₂ solution.