Influence of H<sub>2</sub>S on the Hydrogen Embrittlement Susceptibility of X80 Pipeline Steel in Hydrogen-Doped Natural Gas
Juan Zhou, Mingkun Wu, Jiangbo Qiu, Ran Cheng, Mengkui Tian
Abstract
High Resolution Image Download MS PowerPoint Slide This study investigated the behavior of H 2 S on the hydrogen embrittlement susceptibility of X80 pipeline steel in hydrogen-doped natural gas and thoroughly discussed the mechanism of its influence. The results indicated that H 2 S accelerated the hydrogen embrittlement of X80 steel, and the higher its content, the more severe the embrittlement of the material. Besides, when H 2 S gas was introduced into the hydrogen-doped natural gas, the fracture in the brittle region near the surface presented a mixture of quasi-cleavage and cleavage fracture morphologies, which exhibited typical hydrogen embrittlement characteristics. Furthermore, it was inferred from the results of mechanical properties and fracture morphology analysis that H 2 S competed with H 2 and CH 4 for adsorption sites at large-angle grain boundaries, which increased the ability of iron atoms to provide electrons to hydrogen molecules adsorbed on the steel surface and thus promoted hydrogen embrittlement.