Enhanced cryogenic tensile properties with multi-stage strain hardening through partial recrystallization in a ferrous medium-entropy alloy

We demonstrate the formation of partially recrystallized bimodal microstructures through single-step heat treatment after cold-rolling in Fe60Co15Ni15Cr10 (at%) ferrous medium-entropy alloy that leads to the enhanced yield-strength of ~1.1 GPa and ultimate-tensile-strength of 1.7 GPa at persistent ductility of 61%, evading strength-ductility trade-off. The retention of deformation substructures allows a yield-strength increase by ~79% compared to that in a fully-recrystallized state, together with the modification of mechanical stability without compositional variation, resulting in multi-stage strain hardening capability during tensile deformation at 77 K. [Display omitted]