About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
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Symposium
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Mechanical Response of Materials Investigated through Novel In-situ Experiments and Modeling
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Presentation Title |
In-situ TEM Deformation of High Entropy Alloys Across Multiple Temperature Regimes |
Author(s) |
Madelyn Payne, Lilian Vogl, Peter Schweizer, Mingwei Zhang, Punit Kumar, Mark Asta, Robert Ritchie, Andrew Minor |
On-Site Speaker (Planned) |
Madelyn Payne |
Abstract Scope |
The CrCoNi medium entropy alloy (MEA) is known for having exceptional properties at cryogenic temperatures, including the highest fracture toughness recorded in history. Even at room temperature these alloys are known to display microstructures including nanotwins and stacking faults that contribute to strain hardening. Defect structures such as stacking fault tetrahedra and Lomer-Cottrell locks, introduced by sample processing temperatures and techniques, can influence deformation processes. For example, studies have shown that cryogenic rolling of these alloys produce Lomer-Cottrell locks that enhance strain hardening at room temperature. In this study, we use advanced in-situ TEM techniques to observe dislocation motion and interactions with existing microstructural features in differently processed CrCoNi bars pulled in tension. We perform in-situ TEM tensile deformation at both cryogenic and high temperatures and use advanced characterization techniques including 4DSTEM and image correlation to identify changes in structural features and local strain values. |
Proceedings Inclusion? |
Planned: |
Keywords |
Mechanical Properties, High-Entropy Alloys, Characterization |