Superior strength-ductility synergy by hetero-structuring high manganese steel
Xing Fang, Qiqi Xue, Kaiyuan Yu, Runguang Li, Daqiang Jiang, Lei Ge, Yang Ren, Changfeng Chen, Xiaolei Wu
Abstract
Lacking of forest hardening makes low ductility in steels long challenge particularly at high yield strength. Here, we report to make good use of hetero-structuring for superior strength-ductility synergy in high manganese steel. The point is to retain original deformed structure of large quantity, along with recrystallized ultrafine-grains and fine grains, jointly for most effective heterogeneous deformation-induced (HDI) hardening especially at high strength. The residual plastic strain of larger than 0.2% and large proportion of HDI stress over 60% indicate the crucial role in ductility by HDI hardening. This renders a significantly upgraded strength-ductility combination within high strength scope.\nImpact statement By using the hetero-structuring strategy, a superior strength-ductility synergy is realized specifically at ultra-high strength in high manganese steel.