Twinning Engineering of a CoCrFeMnNi High-Entropy Alloy

SCRIPTA MATERIALIA

卷:197

Article

Moon, Jongun^1,2  Bouaziz, Olivier^3,4  Kim, Hyoung Seop^1,2,5  Estrin, Yuri^6,7 

[1] Pohang Univ Sci & Technol POSTECH, Dept Mat Sci & Engn, Pohang 37673, South Korea

[2] Pohang Univ Sci & Technol POSTECH, Ctr High Entropy Alloys, Pohang 37673, South Korea

[3] Univ Lorraine, CNRS, Labe Etud Microstruct & Mecan Mat LEM3, Arts & Metier Paris Tech, Metz, France

[4] Univ Lorraine, LAB EXcellence DAMAS, F-57000 Metz, France

[5] Pohang Univ Sci & Technol POSTECH, Grad Inst Ferrous Technol, Pohang 37673, South Korea

[6] Monash Univ, Dept Mat Sci & Engn, Clayton, Vic 3800, Australia

[7] Univ Western Australia, Dept Mech Engn, Crawley, WA 6009, Australia

关键词: High-entropy alloys;    Twinning;    Recovery;    Strain hardening;    Ductility;   

DOI  :  10.1016/j.scriptamat.2021.113808

来源: Elsevier

【 摘 要 】

Deformation-induced twinning has been a notable example of overcoming the strength/ductility tradeoff dilemma as a strengthening mechanism. By borrowing this concept from the area of TWIP steels, we designed a thermomechanical treatment for a CoCrFeMnNi high-entropy alloy to improve its mechanical characteristics. We used pre-straining at 77 K to introduce deformation-induced twins in the microstructure of the alloy, and then recovered it by annealing at 773 K, while avoiding recrystallization. The deformation-induced twins generated by pre-straining at 77 K were retained after this heat treatment, whilst partial recovery of dislocations occurred. As a result, the room-temperature mechanical properties of the alloy, including its strain hardening ability, were improved substantially. (c) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

Free