The hypothesis that hydrogen evolution from the chemical attack in aqueous media and subsequent absorption in the metal at the crack tip is a critical reaction leading to stress corrosion cracking (SCC) of Type 304L stainless steel has received increasing support in recent years.1-4 Rhodes1 proposed that the role of hydrogen is to facilitate the formation of martensitic platelets along slip bands at the crack tip. Hydrogen induced martensitic transformations have been observed5 and Birley and Tromans4 have shown that α′ martensite is the dominant component of stress corrosion fracture surfaces.
The importance of martensitic transformations in hydrogen embrittlement of Type 304L stainless steel has also been emphasized.6,7 Benson, et al6 concluded that when Type 304L stainless steel is plastically deformed in hydrogen, microcracks initiate at the martensitic structure, and the cracks propagate along the martensite in a quasicleavage mode causing a reduction...
