Simultaneously increasing both strength and ductility of Fe-Mn-C twinning-induced plasticity steel via Cr/Mo alloying

The effects of Cr/Mo alloying on the tensile deformation behavior of Fe-Mn-C twinning-induced plasticity steel were investigated. The results showed that Cr/Mo alloying increases both the strength and ductility significantly and concurrently. As compared with the premature saturation of deformation twinning in the Cr/Mo-free steel, a unique twinning behavior occurs in the Cr/Mo-alloyed steel, i.e., retarded but more persistent formation of thinner twins with straining. This unique twinning behavior gives rise to a sustained high strain-hardening rate up to higher strains, which delays the plastic instability and increases both strength and ductility simultaneously. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.