Formation of strain-induced martensite in chromium–nickel steels of the austenitic class

We investigate the formation of the first portions of strain-induced martensite in plastic uniaxial compression of 12Kh18N10T and 12Kh18N9T steels in which δ-ferrite is absent and present, respectively, in the initial state. The true deformation martensitic points εs are experimentally determined. It is established that, in 12Kh18N10T steel, there exist one-phase (A) and two-phase (A + M) states for ε < εs and ε > εs , respectively, whereas, in 12Kh18N9T steel, there exist two-phase (A + F) and three-phase (A + F + M) states for ε < εs and ε > εs , respectively. The effect of increase in the magnetization of paramagnetic austenite before the formation of strain-induced martensite is detected.