Revisiting the Considère criterion from the viewpoint of dislocation theory fundamentals

We demonstrate that the Considère condition for plastic instability, which is traditionally obtained from solid mechanics considerations, also follows from the intrinsic evolution laws for dislocation density. Taking strain-rate effects into account, a modified instability condition emerges in a form that resembles Hart’s criterion, but is not identical to it. The Considère strain predicted from the dislocation-based model shows good agreement with experimental data, highlighting the primary role played by dynamic recovery in the mechanical response.