Deformation Twinning Behavior of Twinning-induced Plasticity Steels with Different Carbon Concentrations - Part 2: Proposal of Dynamic-strain-aging-assisted Deformation Twinning

In a previous study, the carbon concentration dependence of the deformation twinning behavior in twinning-induced plasticity steels was investigated, which clarified that the deformation twin fraction in the < 144 > tensile orientation did not change with the carbon concentration. In this study, twinning deformation occurred in the Fe-18Mn-1.2C steel at 473 K with a relatively high stacking fault energy of 55 mJ/m(2). To explain these experimental results, dynamic strain aging of Shockley partials dislocations was proposed as an additional contributing factor to assist the deformation twinning in high-carbon-added austenitic steels. Most abnormalities concerning deformation twinning such as the high stacking fault energy in Fe-Mn-C austenitic steels were interpreted by considering the effect of dynamic strain aging.