Hydrogen absorption and embrittlement of Zn-Al coated medium-Mn steel

In this study, we investigated the influence of the austenitizing condition on H absorption and hydrogen embrittlement (HE) in a Zn-Al coated medium-Mn steel. The specimen, which underwent austenitization at 750 °C for 5 min, demonstrated high resistance to HE due to its low diffusible H content. The presence of a uniform Al2O3 oxide layer and a low H diffusion rate contributed to this low H content. However, an increase in austenitizing temperature accelerated H absorption due to the enhanced diffusion rate of H atoms, resulting in decreased resistance to HE.