Yield strength-ductility trade-off breakthrough in Co-free Fe40Mn10Cr25Ni25 high-entropy alloys with partial recrystallization

High performance materials with low cost have been the goal of the pursuit of engineering materials. In this study, an economic cost-effective Co-free Fe40Mn10Cr25Ni25 (at%) high-entropy alloy (HEA) was developed. According to the concept of heterogeneous microstructure design, a partially recrystallized microstructure was developed by cold-rolling, followed by subsequent annealing. Surprisingly, the current alloy displays a yield strength of 710 MPa, an ultimate tensile strength of 880 MPa, and a uniform elongation of 18%. The overcome of yield strength-ductility trade-off is achieved by the heterogeneous microstructure composed of coarse non-fully recrystallized grains and fine recrystallized grains. The reinforcement of strength stems from the hindering effect on the dislocation movement caused by the deformation inhomogeneity. A resultful strategy is presented to constitute a cost-effective HEA with a good combination of high strength and ductility in this study.

Automated summary

An economic cost-effective Co-free Fe40Mn10Cr25Ni25 high-entropy alloy was developed in this study, achieving a good combination of high strength and ductility through heterogeneous microstructure design.