Sulphide corrosion cracking of steel and methods of its corrosion protection

Foreign data are generalized on fracture effect of hydrogen adsorbed by steel corrosion affected by H2S containing environments, on methods used to reveal propensity of steel for sulphide corrosion cracking as well as to protect it. Cracking is prevented through rational choice of steel composition, product design and its operation conditions. As for low alloyed steel of medium strength most rational are deep desulphurization (up to 2×10-3%), alloying with Cu above 3% and control of shape and non-metallic inclusions through modification with calcium at Ca÷S≥2. Chromium-nickel austenitic materials fracture in H2S-chloride mixture at ≥150°.