Hierarchical structured as-cast CrFeNiMn0.5Cu0.5 high entropy alloy with excellent tensile strength/ductility properties

Hierarchical structure with microscale granular phase separation and nanoscale intragranular precipitation developed during casting and cooling in CrFeNiMn0.5Cu0.5 high entropy alloy (HEA) due to the reduction of entropy contribution during solidification. Hierarchical-structured CrFeNiMn0.5Cu0.5 prepared by conventional induction casting exhibited extraordinary as-cast tensile strength/ductility trade-off (1.02 GPa/28%) that beats most thermo-mechanically processed HEAs. In all three ductile granular phases (dual fcc and a bcc), needle-shaped precipitates with different compositions were observed. Compositionally inverse relationship between precipitates and matrix in dual fcc phases developed due to decreasing mutual solubility with decreasing temperature. The predicted yield stress (568.6 MPa) of hierarchical-structured alloy with precipitate strengthening in three different phases agrees well with the experimental stress (582 MPa). (C) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.& nbsp;

Automated summary

Hierarchical structure with microscale granular phase separation and nanoscale intragranular precipitation developed in CrFeNiMn0.5Cu0.5 high entropy alloy due to the reduction of entropy contribution during solidification. The conventional induction casting method produced hierarchical-structured high entropy alloy with extraordinary mechanical properties, surpassing most thermo-mechanically processed high entropy alloys.