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

• Published in: Journal of materials science & technology Vol. 87; pp. 29 - 38
• Main Authors: Wang, Qiang, Zeng, Liangcai, Gao, Tengfei, Du, Hui, Liu, Xinwang
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 10-10-2021
• Subjects: Deformation mechanism; Dislocation; High-entropy alloy; Microstructure; Stacking fault; Stacking fault; Microstructure; High-entropy alloy; Deformation mechanism; Dislocation
• ISSN: 1005-0302; 1941-1162
• DOI: 10.1016/j.jmst.2021.01.053

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•The HEA consisted of 77.3 vol.% FCC plus 22.7 vol.% B2.•The HEA exhibited excellent tensile properties.•Disordered dislocations were to form dislocations wall.•Dissociation of dislocations generated stacking fault.
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 ∼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.