Improved resistance to hydrogen environment embrittlement of warm-deformed 304 austenitic stainless steel in high-pressure hydrogen atmosphere

The resistance of warm-deformed 304 austenitic stainless steel to hydrogen environment embrittlement (HEE) was investigated by adjusting the deforming temperature and deforming strain in hydrogen atmosphere. Higher deforming temperatures (100∼300 °C) can improve the resistance to HEE, while higher deforming strains weakened the resistance to HEE. Higher deforming temperatures caused a more uniform distribution of the high-density dislocations and less deformation twins, which weakened hydrogen segregation to prevent hydrogen-induced cracking. As the deforming strain increased, more primary deformation twins formed, which promoted the formation of strain-induced α′ martensite and then accelerated the growth of hydrogen-induced cracks.