Abstract
Susceptibility of welding joints of low-carbon steels to stress-corrosion cracking (SCC) is not clearly established. Such steels are generally not susceptible to that type of corrosion, but many failures have been observed in welding zones where subcritical crack growth was suspected to be a cause of catastrophic crack propagation. This work consists of the first set of research results performed on samples cut from welded 40 mm thick steel sheets exposed to a 3.5% NaCl water solution. The specimens with the tip of V-notch placed method in a fusion zone were tested by the cantilever beam method in an open circuit condition. The mechanism of SCC susceptibility ratio Kscc/Kc was 0.72. This value belongs to the highest class of susceptibility to SCC. The mechanism of crack propagation is believed to be a mixed mode of ‘hydrogen-induced embrittlement’ due to active path (or ‘martensitic’) structure and ‘pre-existing cracks are present.