It is often a complex problem due to the coupling of martensitic transformation and hydrogen diffusion. Hydrogen embrittlement in martensitic press-hardened steel (PHS) presents a great challenge to the automotive industry that employs largely PHS in the critical parts of body-in-white. Furthermore, this paper highlights the synergistic activity of the HELP and HEDE mechanisms of HE in steel and the importance of developing structures for storing hydrogen on a large scale. The significance of the research is highlighted by its practical application for assessing the durability of steel structures and infrastructure against hydrogen environment-assisted cracking (HEAC). Furthermore, fractography of the specimens was performed to observe the synergistic action of HELP and HEDE mechanisms of hydrogen embrittlement (HE), and their subsequent effects on the microstructure and fracture resistance of steel. Based on test results, models for the degradation of KQ of steel were developed in accordance with the proposed hydrogen-enhanced localized plasticity (HELP) and hydrogen-enhanced decohesion (HEDE) model (HELP + HEDE model) of hydrogen embrittlement. Before KQ testing at various intervals, the hydrogen contents of the specimens were determined by an electrochemical approach. Specimens were tested for crack tip opening displacement (CTOD) fracture toughness at six- and twelve-month intervals of immersion in acidic environments.

Steel specimens were coated from all sides except one surface to accurately quantify the influence of hydrogen diffusing from the environments into the specimens. This paper investigates the influence of hydrogen on the candidate fracture toughness (KQ) of low carbon steel immersed in acidic hydrogen environments for one year which has limited previous research.

However, the storage and transportation of hydrogen gas are challenging because of its very nature and impact on pipelines and storage tank/facility materials. Hydrogen gas is a renewable energy source for electrical and transportation fuel for vehicular applications.

Acid pickling of martensitic steel