Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1448525 | Acta Materialia | 2008 | 8 Pages |
The effect of nickel equivalent on hydrogen gas embrittlement (HGE) of austenitic stainless steels of Fe–(10–20)Ni–17Cr–2Mo alloys vacuum-melted in a laboratory, based on type 316 stainless steel, was investigated. Tensile tests were conducted in hydrogen and helium at 1 MPa in the temperature range from 80 to 300 K. It was found that HGE of the alloys below a nickel equivalent of 27% increased with decreasing temperature, reached a maximum at 200 K, and then decreased with further decreasing temperature, whereas no HGE occurred above the nickel equivalent of 27%. It was observed that the content of strain-induced α′ martensite increased with decreasing temperature and nickel equivalent, and hydrogen-induced fracture occurred mainly along α′ martensite structure. Thus, the susceptibility to HGE depended on nickel equivalent. It was discussed that HGE was controlled by strain-induced α′ martensite above 200 K, whereas it was controlled by hydrogen transport below 200 K.