About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
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| Symposium
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Bridging Scales: Deformation and Damage Mechanisms in Microstructurally and Compositionally Complex Metallic Alloys
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| Presentation Title |
Ductility mechanisms in complex concentrated refractory alloys from atomistic fracture simulations |
| Author(s) |
Wenqing Wang, Punit Kumar, David Cook, Flynn Walsh, Buyu Zhang, Pedro Borges, Diana Farkas, Robert O. Ritchie, Mark Asta |
| On-Site Speaker (Planned) |
Wenqing Wang |
| Abstract Scope |
The striking variation in damage tolerance among refractory complex concentrated alloys is examined through the analysis of atomistic fracture simulations, contrasting behavior in elemental Nb with that in brittle NbMoTaW and ductile Nb45Ta25Ti15Hf15. We employ machine-learning interatomic potentials (MLIPs), including a new MLIP developed for NbTaTiHf, in atomistic simulations of crack tip extension mechanisms based on analyses of atomistic fracture resistance curves. While the initial behavior of sharp cracks shows good correspondence with the Rice theory, fracture resistance curves reveal marked changes in fracture modes for the complex alloys as crack extension proceeds. In NbMoTaW, compositional complexity appears to promote dislocation nucleation relative to pure Nb, despite theoretical predictions that the alloy should be relatively more brittle. In Nb45Ta25Ti15Hf15, alloying alters the fracture mode compared to elemental Nb, promoting crack tip blunting and enhancing resistance to crack propagation. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, Mechanical Properties, Modeling and Simulation |