Achieving superior ductility with ultrahigh strength via deformation and strain hardening in the non-recrystallized regions of the heterogeneous-structured high-entropy alloy

Authors: Hongchao Li, Jun Wang, Wenyuan Zhang, Jiawang Zhao, Jinshan Li, M. W. Fu

The trade-off between ultrahigh strength and exceptional ductility is always a challenge for the development of metallic structural materials. By using compound processes, cold rolling followed by annealing, heterogeneous microstructures consisting ultrafine recrystallized grains and extensive non-recrystallized regions could be obtained. These architected microstructures contributed to increasing yield strength by micro-scaled mechanisms like dislocation strengthening, precipitation strengthening, and grain boundary strengthening. On the other hand, the non-recrystallized regions could accommodate high strain via reactivating the pre-existing deformation bands and the synergistic deformation of the FCC and partitioned phases, which enhanced the ductility consequently. These findings verified that multi-stage processing of materials could be used in preparing materials of considered in functional structure fabrication, and the usage of micro-scaled enhancing mechanisms could realize satisfied mechanical properties in base materials possibly.