Research on the influence of finish rolling technique parameters on H₂S corrosion resistance behavior of pipeline steel in the thickness direction

Abstract Natural gas was an important energy for human society’s development, and there was still a great demand for this type of energy. It required pipeline steel for energy transport and had excellent hydrogen-induced cracking resistance. Thermomechanical controlled processing (TMCP) was a frequently used manufacturing method for pipeline steel. It was necessary to research the effect of finish rolling technique parameters on the H 2 S corrosion resistance behavior of pipeline steel in the thickness direction, especially concerning microstructure and hardness in the thickness direction. So, for the research, optical microscope (OM), hydrogen-induced cracking tests (HIC), and hardness tests were used to study the effect of finish rolling technique parameters on H 2 S corrosion resistance. As finish rolling deformation increases, deformation can effectively conduct from surface to center and reduce the average hardness gap between the surface and the center. It can also generate finer microstructure and smaller hardness differentials from the thickness direction. All these can enhance the hydrogen-induced cracking resistance.