About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Thermodynamics and Kinetics
|
Presentation Title |
Effect of Electric Fields on Bulk and Surface Driven Dislocation Behavior in fcc Metals |
Author(s) |
Soumendu Bagchi, Danny Perez |
On-Site Speaker (Planned) |
Soumendu Bagchi |
Abstract Scope |
High-gradient electric-fields are inevitably encountered in technologies ranging from low-cost compact linear accelerators to miniaturized electronic devices. Material functionality under extreme field conditions can heavily depend on the coupling between electro-thermal loading and microstructural deformation. While difficult to explicitly access through state-of-the art experiments, relevant mechanisms of field-induced material evolution can be directly probed by atomistic simulations. Using a charge-equilibration-molecular dynamics framework, we model the effect of surface electric fields and thermo-mechanical stresses on the plastic deformation of fcc metals. Bulk dislocation multiplication mechanisms e.g. Frank-Read source activation is shown to enhance local field-induced stresses through the creation of surface slipped-steps, which can facilitate further activation. We also investigate the possibility to nucleate dislocation loops from slipped surface-steps by quantifying the related activation energy barriers. By performing fixed-end nudged elastic band calculations, we show that nucleation barriers can be significantly reduced with increasing surface electric field and slip-step heights. |
Proceedings Inclusion? |
Planned: |
Keywords |
Electrometallurgy, Modeling and Simulation, Computational Materials Science & Engineering |