Investigation into effect of hydrogen concentration on HIC susceptibility of 08Cr2AlMo steel in saturated H2S solution

08Cr2AlMo steel is a type of material developed especially for heat exchanger pipe bundle used in the mediums containing H2S in the recent years. The relationship between hydrogen concentration and hydrogen induced cracking (HIC) susceptibility of 08Cr2AlMo steel with different plastic deformation in saturated H2S solution was investigated by means of improved electrochemical test, tensile test and scanning electron microscopy (SEM) technology. Improved electrochemical method introduced in this paper is a simple and effective method for measuring hydrogen concentration in steel. For the material with the same plastic deformation, the longer the immersion time, the more hydrogen atoms will migrate into the steel. For the same immersion time, the larger the plastic deformation, the higher the hydrogen concentration in the steel is. HIC susceptibility is linearly related to the hydrogen concentration in 08Cr2AlMo steel in saturated H2S solution. For HIC type of stress corrosion cracking (SCC), by measuring I-HIC in various hydrogen concentrations at different immersion time, HIC susceptibility of the material in service can be predicted, and then the structural integrity of pressure-containing component can be estimated.