Hydrogen embrittlement in 0.31% carbon steel used for petrochemical applications

The presence of hydrogen will cause damaging effects in steels and its alloys used in petroleum refineries, natural gas pipelines and oil fields. The present investigation was carried out to assess the effect of hydrogenation time, independent of other processing and other constitutional variables, on the mechanical properties of 0.31% carbon steel. The results revealed that as the exposure time for cathodically charged hydrogenated steel was increased, an increase in tensile strength, yield strength and breaking strength was observed with a loss in ductility. A decrease in the mechanical properties was also noticed when the specimens of medium carbon steel were charged with hydrogen for a longer period with exception of ductility. SEM studies on the fractured surfaces of the hydrogen charged specimens exhibited surfaces ranging from intergranular tear to high-pressure fractured locations.