Suppression of Serrated Flow in Medium Mn Steel Under Pulsed Electric Current

Abstract

Based on the electroplasticity effect and dynamic strain aging interpretations, serrated flow under the influence of electroplasticity in medium Mn steel is investigated. With the decrease of dislocation waiting time and the increase of critical strain, the continuity of plastic deformation stage can be extended by the action of electron wind force. Meanwhile, the dislocation density that affects the plastic instability due to the interaction of mobile dislocations with obstacles is greatly reduced, which plays a dominant role in suppressing Portevin-Le Chatelier effect. Through the experimental results of pulsed current suppression of PLC effect in medium Mn steel, the mathematical model of current density and dislocation waiting time is established. It is found that the current density is proportionate to the reduction of dislocation waiting time.

Keywords: Portevin-Le Chatelier effect, medium Mn steel, Electric current, Dislocation.