Influence of strain rate on the activation of {110}, {112}, {123} slip in ferrite of DP800

Abstract We have performed micro pillar compression to investigate the influence of strain rate on the activation of three slip plane families, namely {110}, {112} and {123}, in ferrite of a dual phase steel. The critical resolved shear stress of all three slip plane families rises with increased strain rate. The strain rate sensitivity drops with increasing strain. Increasing strain rate does not reduce the number of activated slip systems, instead resulting in slip plane activation outside of that predicted by Schmid´s law. The activation volume of 13b³ to 16b³ suggests that the Peierl's process is the rate controlling mechanism in ferrite of DP800.