Transformation mechanism of α′-martensite in an austenitic Fe–Mn–C–N alloy

The strain-induced transformation from austenite (fcc) into α′-martensite (bcc) in an Fe–18Mn–0.25C–0.084N austenitic alloy has been studied through transmission electron microscopy. It was found that α′-martensite nucleated in the intersection of two ε-martensite laths. Detailed observations of the crystal structures in this zone allowed the incorporation of the relaxation of the transformation strains by the introduction of retransformation partial dislocations.