About this Abstract |
Meeting |
2018 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Design and Simulation of Materials (CDSM 2018): Atomistic Simulations
|
Presentation Title |
First-principles Study of Dislocations in BCC Fe |
Author(s) |
Michael Richard Fellinger, Anne Marie Z. Tan, Louis G. Hector, Dallas R. Trinkle |
On-Site Speaker (Planned) |
Michael Richard Fellinger |
Abstract Scope |
We relax core structures of 1/2[111] screw, [100](010) edge, [100](011) edge, [-1-11](1-10) edge, and 71° mixed dislocations in bcc Fe using first-principles calculations coupled with flexible boundary conditions. The relaxed geometries reveal atomistic details in the dislocation cores, and can be used to generate data for mesoscale models to study the interplay between solutes and dislocations in Fe. We illustrate this for the 1/2[111] screw dislocation by computing energy landscapes for substitutional Al, B, Cu, Mn, and Si solutes and octahedral interstitial B, C, and N solutes near the core. The calculations provide interaction energies that can be used to extract solid solution strengthening parameters for bcc Fe, and show that interstitial and substitutional solutes can cause the dislocation core to translate and/or reconstruct depending on their concentration and proximity to the core. We also present the influence of the dislocations and solutes on local magnetic moments near the core. |
Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |