About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
|
Symposium
|
Mechanical Behavior at the Nanoscale VI
|
Presentation Title |
Deformation Twins in BCC Metals - Atomic Level Origins |
Author(s) |
Christopher R. Weinberger, Anik Faisal |
On-Site Speaker (Planned) |
Christopher R. Weinberger |
Abstract Scope |
It is well known that BCC transition metals deform via deformation twinning at sufficiently low temperatures or high strain rates. Furthermore, as crystallite size approaches the nanoscale, deformation twining has been shown to be competitive with dislocation slip. However, there are still open questions regarding the structure of deformation twins and how they compete with dislocation slip. Here, examine the atomic level structure of twins in BCC metals using density functional theory, demonstrating that twin structure depends on chemistry. Using DFT, classical atomistics, and continuum models, we examine the nucleation processes and energetics of twin nucleation. This provide insight into how the structure affects nucleation, the stresses required for nucleation as well as provides insight into how twin nucleation stresses compare to the bulk stresses. These results are further compared with similar calculations for dislocation nucleation, which provides insight into the competition between twinning and slip at the nanoscale. |
Proceedings Inclusion? |
Planned: |
Keywords |
Mechanical Properties, Modeling and Simulation, Computational Materials Science & Engineering |