| About this Abstract |
| Meeting |
2021 TMS Annual Meeting & Exhibition
|
| Symposium
|
Defect and Phase Transformation Pathway Engineering for Desired Microstructures
|
| Presentation Title |
Evolving Core Structures in Dislocation-twin Boundary Interactions |
| Author(s) |
Orcun Koray Celebi, Ahmed Sameer Khan Mohammed, Francisco Andrade Chávez, Jessica A. Krogstad, Huseyin Sehitoglu |
| On-Site Speaker (Planned) |
Orcun Koray Celebi |
| Abstract Scope |
The superior performance of nanotwinned microstructures is fundamentally attributable to the dislocation-Twin Boundary (TB) interactions. However, this interaction exhibits a complex dependence on microstructural parameters such as twin crystallography and load orientation. Consequently, current state-of-the-art models follow a case-by-case analysis of each possible interaction, requiring expensive atomistic or dislocation-dynamics simulations. Furthermore, the existing models are not truly predictive in that they employ some form of empiricism. We develop a predictive analytical framework devoid of empiricism, extending the idea of a Generalized Peierls-Nabarro model. Analytical predictions are validated against atomistic simulations employing Molecular Dynamics (MD). We propose for the first time, the non-planar core structures of sessile dislocations of the reactions. We uncover the sensitivity of twin interaction stresses on planar fault energies, aimed to inform exploration of the compositional design space for superior nanotwinned alloys. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, Thin Films and Interfaces, Modeling and Simulation |