Tensile testing in high pressure gaseous hydrogen using conventional and tubular specimens: Ferritic steels

Twenty-two commercial steels with a bcc microstructure were tensile tested in reference atmosphere and in gaseous high-pressure hydrogen using conventional (CS) and tubular specimens (TS). For both specimen types, 0.2% yield strength and ultimate tensile strength were comparable. In reference atmosphere, reduction of area (RA) of CS was higher compared to TS, whereas in gaseous high pressure hydrogen RA of CS was lower compared to TS. The mean deviation between RA of TS and RA of CS is 11% for specimens tested in reference atmosphere and 10% for specimens tested in H2 gas. In addition, given the diverse range of steels investigated here, the results shed some light on trends about the influence of microstructure on hydrogen effects.