An Overview of High Yield Strength Twinning-Induced Plasticity Steels

Abstract

Twinning-induced plasticity (TWIP) steel is a second-generation advanced high strength steel grade developed for automotive applications. TWIP steels exhibit an excellent combination of strength and ductility, mainly originating from the activation of deformation twinning. However, TWIP steels generally exhibit a relatively low yield strength (YS), which limits their practical applications. Thus, developing high YS TWIP steels without ductility loss is essential to increase their industrial applications. The present work summarizes and discusses the recent progress in improving the YS of TWIP steels, in terms of precipitation strengthening, solid solution strengthening, thermomechanical processing, and novel processes. Novel processes involving sub-boundary strengthening, multi-phase structure, and gradient structure as well as the control of thermomechanical processing (recovery annealing and warm rolling) and precipitation strengthening were found to result in an excellent combination of YS and total elongation.