Substructure induced twinning in low density steel

The stacking fault energy of low density steels is sufficiently high to suppress twin formation thereby the twinning induced plasticity effect is expected to disappear. The present work devotes to address the origin of deformation twinning in a duplex low density steel. The substructure evolution (i.e. formation, refinement, size stabilization and its rotation) provides local areas holding preferred orientation for twin nucleation. Twinning is more populated in regions possessing higher Schmid factor for slip than that of twin. The observed non-Schmid behavior is attributed to the substructure induced nature of twinning and increased feasibility of extrinsic stacking fault formation