Studies on the effect of high-temperature and pressure hydrogen environments on 09G2s steel properties

The susceptibility of 09G2S steel to hydrogen corrosion after the saturation of specimens with gaseous hydrogen under a 5-MPa uniform pressure at 300, 400, and 500°C was investigated during different holding times. This effect on the metal structure and properties was studied. It was shown that the saturation of specimens with hydrogen caused gradual carbon depletion of steel, the metal structure displayed a larger number of ferrite grains with well-defined boundaries. The onset of intense hydrogen corrosion appears as a smaller number of pearlite grains in the metal structure. The experimental data resulted in establishing the incubation period of hydrogen corrosion of 09G2S steel, i.e., time to the onset of decarbonization under preset conditions of the metal saturation with gaseous hydrogen under a 10-MPa pressure at ° , which is 90 and 17 h, 500 and 580°C respectively. The reserve of 09G2S steel hydrogen stability within the incubation period is the basis for adding to safe service life of equipment for petrochemical and oil refining industries in hydrogenation processes.