On the room-temperature tensile deformation behavior of a cast dual-phase high-entropy alloy CrFeCoNiAl0.7

The microstructure and room-temperature tensile deformation behavior of the cast CrFeCoNiAl0.7 high-entropy alloy (HEA) were studied in details. The cast HEA consisted of a dual-phase structure of 77. 3 vol. % face-centered-cubic (FCC) phase plus 22.7 vol.% B2 phase, and exhibited excellent room-temperature tensile properties with a high yield strength of 876 MPa, ultimate tensile strength of 1198 MPa and a relatively large elongation to fracture of similar to 9 %. Dislocations gliding in the FCC phase governed the plastic deformation at the early stage of room-temperature tensile, and disordered dislocations were to form dislocation walls as the deformation proceeded. With further increase in strain to a high level, the stacking faults were generated through the dissociation of the geometrically necessary dislocations, serving as the potential heterogeneous nucleation sites for the deformation twins. (C) 2021 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.