Stress corrosion cracking behavior of X80 steel under the combined effects of sulfide and cathodic potential

Electrochemical corrosion and stress corrosion cracking (SCC) behavior of X80 steel in the sulfurated marine environment at open circuit potential and −850 mVSCEare investigated. The results show that SCC is controlled by both anodic dissolution and hydrogen evolution, which is attributed to the HSO3−acceleration of the anodic and cathodic current density. Localized anodic dissolution leads to pits, which induce stress that promotes the initiation of stress corrosion cracks. Under a cathodic potential of −850 mVSCE, the effect of dissolution is limited, and SCC susceptibility increases because of the synergistic effect of the high HSO3−concentration and cathodic potential.