About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
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Hume-Rothery Symposium: Interface Structure and Properties: Impact on Microstructure Evolution
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| Presentation Title |
Multi-Scale Simulations of Deformation and Failure Behaviours in Polycrystalline Multi-Principal Element Alloys |
| Author(s) |
Yilun Xu, Wanghui Li, Xiaochong Lu, Zachary Aitken, Guglielmo Vastola, Huajian Gao, Yong-Wei Zhang |
| On-Site Speaker (Planned) |
Yong-Wei Zhang |
| Abstract Scope |
In this talk, I present recent multi-scale simulation studies aimed at understanding plastic deformation and failure behaviours in polycrystalline MPEAs. We first investigate the Hall-Petch to inverse Hall-Petch transition in nanocrystalline CoCrFeMnNi under shock loading using molecular dynamics simulations, revealing a strong dependence on shock pressure due to competing hardening (dislocation interactions, GB blocking) and softening (phase formation, amorphization, GB thickening, grain rotation) mechanisms. In the second study, combining experiments with CPFE and DDP simulations, we examine how layer strength ratio affects dislocation accumulation and stress fields at hetero-zone boundaries. Strain gradients near boundaries enhance hardening via dislocation pile-up and long-range stress. Lastly, a temperature-sensitive crystal plasticity model is developed to capture tensile and cyclic behaviour of Cantor alloy-like MPEAs, linking dislocations, twinning, phase transformation, GBs, and SRO to mechanical performance and fatigue resistance. These studies offer insight into GB-related mechanisms and guide the design of advanced structural alloys. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, Mechanical Properties, High-Entropy Alloys |