Tensile and fracture behaviors of austenitic high-manganese steels subject to different hydrogen embrittlement test methods

Abstract

The hydrogen-embrittlement susceptibility of austenitic high-manganese steels according to different hydrogen-charging test methods was discussed in terms of hydrogen-embrittlement process and fracture mechanism. Ex-situ electrochemical and high-pressure thermal hydrogen-charging methods exhibited a difference in hydrogen-embrittlement susceptibility because they affect the permeability and diffusivity of hydrogen. Moreover, the in-situ high-pressure gaseous hydrogen-charging method showed the most apparent hydrogen-embrittlement susceptibility because higher triaxial stress in the necked region caused by plastic instability accelerates hydrogen charging in the specimen during tensile testing in hydrogen environment, thus leading to intergranular fracture in all regions.