X-RAY STUDY OF HYDROGEN INDUCED PHASE TRANSFORMATION AND ITS SEQUENCE, IN AUSTENITIC STAINLESS STEEL.

An X-ray study of the process of martensite transformation induced by hydrogen charge in austenitic stainless steel has been carried out, and it has been established that the sequence of the transformation is gamma yields epsilon prime yields epsilon plus alpha . The phase is probably an unstable phase which is a sort of the intermediate phase of hydride, but the epsilon and alpha are both thermally stable martensite phases. The two phases, epsilon and alpha , have the same type of crystal lattice and the same values of lattice constants with strain-induced martensite phases.