About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
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Symposium
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Heterostructured and Gradient Materials (HGM V): New Mechanistic Discoveries Enabling Superior Properties
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Presentation Title |
Design of Heterostructured High Entropy Alloys for Superior Mechanical Properties at Cryogenic-to-ambient Temperatures |
Author(s) |
Cheng Zhang, Enrique Lavernia |
On-Site Speaker (Planned) |
Enrique Lavernia |
Abstract Scope |
The highly tunable properties of high-entropy alloys (HEAs) provide extraordinary potential for critical structural applications, especially under extreme conditions. However, it is still a challenge for HEAs to achieve ultrahigh engineering tensile strength over 2 GPa with reasonable ductility. Here, with the introduction of heterogeneous microstructure, we report on a FeNiCoAl-based HEA that can show a superb combination of mechanical properties at cryogenic-to-ambient temperatures. Experimental results, obtained from TEM, TEM-based PED, and EBSD, demonstrate that the heterogeneous microstructure triggers high hetero-deformation induced hardening and facilitates the accumulation of dislocations. The macroscopic “loading-unloading-reloading” cyclic tensile tests confirm that hetero-deformation induced hardening plays a significant role in strengthening the alloy during deformation. Details about the difference in the sequence of phase transformation in fine grains and coarse grains caused by heterogeneity will be shown. The strategy for designing heterostructured HEAs with ultrahigh strength-ductility synergy will also be presented. |
Proceedings Inclusion? |
Planned: |
Keywords |
Mechanical Properties, Phase Transformations, High-Entropy Alloys |