About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advances in Multi-Principal Element Alloys V: Mechanical Behavior
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| Presentation Title |
Tunable energy landscape of screw dislocation cores by compositional fluctuations in bcc high-entropy alloys |
| Author(s) |
Pedro Borges, Robert O Ritchie, Mark Asta |
| On-Site Speaker (Planned) |
Pedro Borges |
| Abstract Scope |
The energy landscape of screw dislocation cores plays a central role in dislocation-mediated deformation mechanisms in bcc metals. In bcc high-entropy alloys (HEAs), this energy landscape is modulated by local compositional fluctuations, which has important implications for deformation processes in these materials. Through density functional theory calculations, we investigate high-symmetry screw dislocation core structures in NbTaMoW and NbTaTiHf bcc HEAs. Importantly, group IV elements near the core induce features in the energy landscape that are exclusive to HEAs containing these elements, specifically lowering the energy of core configurations that are unstable in elemental bcc metals. A combined influence of these chemical effects with crystallographic details enables the activation of {112} glide planes, a feature that has been linked to ductility improvements in bcc HEAs. These findings provide new insights into the atomic-scale mechanisms underlying dislocation mobility in bcc HEAs, offering a pathway for designing materials with tailored mechanical properties. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
High-Entropy Alloys, Mechanical Properties, |