Title: XRD-Results measured on fracture surfaces of austenitic tensile test specimen

Abstract

The fraction of α’-Martensite was measured on fracture surfaces of ten commercial austenitic stainless steels of different austenite stability by quantitative X-ray diffraction (XRD). Due to austenitic steels tend to transform partially to α’-Martensite upon straining as under tensile testing. Due to the influence of pressurized hydrogen the partition of α’-Martensite divers from steel to steel, when tensile tested in hydrogen compared to specimen tested in helium atmosphere. The formation of α’-martensite may help to result in hydrogen assisted crack initiation and propagation. For a given steel, α’-martensite contents on fracture surfaces of specimens tested in helium were higher compared to those tested in hydrogen and tensile reduction of area of the specimens tested in hydrogen decreases with increasing martensite content on the fracture surface. The relative reduction of area RRA is presented.