| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Mechanical Behavior Related to Interface Physics IV
|
| Presentation Title |
Examining the Role of Grain Boundaries on the Influence of Screw Dislocation Mobility in Bcc Metals |
| Author(s) |
Xiochuan Tang, Gregory Thompson, Christopher R. Weinberger |
| On-Site Speaker (Planned) |
Christopher R. Weinberger |
| Abstract Scope |
Tungsten is well-known to be brittle at room temperature but, contrary to other metals, actually shows improved ductility with grain refinement. While there is yet to be a thorough explanation, it is thought to be related to dislocation mobility - controlled by screw dislocations. In this talk, we examine the role interfaces play in controlling kink nucleation and how this is influenced by crystallite size. Specifically, we use kinetic Monte Carlo to examine screw dislocation motion in tungsten and tantalum and its dependence on size. Specific attention is put on kink nucleation from the surface and how this affects dislocation mobility These results not only reveal new size effects in dislocation mobility, but also a surprising relationship to the elasticity of the material which controls the absolute size regimes in which this occurs. Finally, these results are related to size effects in BCC plasticity and the BDTT in tungsten. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
High-Temperature Materials, Mechanical Properties, Modeling and Simulation |