Impact of the Microstructure and Surface Finishing on the Ductility Response of AISI type 304L Steel Tested in High Pressure Hydrogen Gas Atmosphere

The presence of hydrogen in iron alloys leads to an impairment of mechanical properties. This can be related to the production routes and material processing. Microsegregations, grain size and surface finishing play a very important role on the ductility response in hydrogen. Particularly, a more homogeneous distribution of alloying elements, a reduction in grain size and a proper surface finishing improve the material's ductility for a fixed composition. The study material is an AISI type 304L austenitic stainless steel subjected to tensile tests in air at ambient pressure and in a 40 MPa hydrogen gas atmosphere at 25 °C.