About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advances in Multi-Principal Element Alloys V: Mechanical Behavior
|
| Presentation Title |
Temperature-dependent screw dislocation dynamics on multiple slip systems in MoNbTi refractory multi-principal element alloy |
| Author(s) |
Pulkit Garg, Daniel Magnuson, Irene J. Beyerlein, Kevin Hemker |
| On-Site Speaker (Planned) |
Pulkit Garg |
| Abstract Scope |
Activation of higher-order slip systems has been observed during room-temperature deformation of body-centered cubic refractory multi-principal element alloys (RMPEAs). Our recent experiments on single-crystalline MoNbTi RMPEA further evidence concurrent activity on multiple slip systems, including {110} and {112} planes at elevated temperatures. In this work, we investigate the temperature-dependent dynamics of screw dislocations on {110} and {112} slip planes in MoNbTi RMPEA using a 3D atomistically informed phase-field dislocation dynamics (PFDD) model coupled with Langevin dynamics. Our simulations show a reduction in critical stress for dislocation glide with increasing temperature, with distinct behavior across the two slip systems. The influence of local chemical fluctuations on dislocation mobility is analyzed to understand how atomic-scale disorder governs glide mechanisms. Post-deformation cooling and unloading are simulated to assess residual dislocation structures, enabling comparison with experimental transmission electron microscopy observations. These insights help connect thermally activated dislocation processes to macroscopic mechanical response of RMPEAs. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Mechanical Properties, High-Entropy Alloys, Computational Materials Science & Engineering |