Abstract: This study investigated stress corrosion cracking (SCC) of A588 steel welds as determined by U-bend
immersion tests and slow strain rate tensile (SSRT) tests to evaluate the steel’s cracking susceptibility in
various regions of the weldments. The immersion test results indicated that the fusion zone (FZ) had better
corrosion resistance than the other regions in the weld. It was also demonstrated that the columnar grain
boundaries exhibited a higher resistance to corrosion than the grain interior of the FZ. However, the
coarse elongated ferrite in the FZ is susceptible to hydrogen embrittlement (HE), which results in the
formation of microcracks. As a result, a severe degradation of the weld’s tensile properties in the saturated
H2S solution was observed. Scanning electron microscope (SEM) fractographs of tensile specimens reveal
a cleavage fracture in the coarse-grained heat-affected zone (CGHAZ) and featherlike rupture in the FZ,
both indicating a high sensitivity to HE.
