Internal microstresses as a reason for the increase in the temperature of the start of the martensite transformation in electrolytic hydrogen impregnation of austenite

An investigation was made of specimens of N31 iron-nickel alloy with a low carbon content, which practically eleiminated its influence on the temperature of the start of the martensite transformation and made it possible to hydrogen impregnate specimens at room temperature and to preserve in the material a sufficient quantity of diffusion mobile hydrogen at the moment of determination of the parameter M /SUB s/ . Figures show change in the concentration of diffusion-mobile hydrogen, and the results obtained make it possible to conclude that the reason for the increase in the temperature of the start of the martensite transformation in electrolytic hydrogen impregnation is the occurrencce of internal microstress es in the metal.