Resetting the Austenite Stability in a Medium Mn Steel via Dislocation Engineering

Abstract

In general, it is very difficult to reset the mechanical stability of retained austenite grains in a given steel grade through the conventional governing factors such as the chemical compositions and grain size. Here we try to resolve this challenge via dislocation engineering. The dislocations are introduced by deformation of a medium Mn steel at a relatively high temperature (~ 300 °C) where the austenite grains are mostly deformed by the dislocation plasticity. These dislocations tend to stabilize the retained austenite grains and therefore reserve a substantial austenite fraction for the transformation-induced plasticity effect at a large strain regime.