About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
2026 Technical Division Student Poster Contest
|
| Presentation Title |
SPG-22: Defect Polyhedra Connect Grain Boundary Structures to Dislocation Content in FCC Metals |
| Author(s) |
Elizabeth Heon, Sheryl Sanchez, Austin Houston, Mahshid Ahmadi, Eric Lass, Matthew Chisholm, Gerd Duscher |
| On-Site Speaker (Planned) |
Elizabeth Heon |
| Abstract Scope |
Grain boundaries are important for mechanical properties; however, there is no general theory predicting grain boundary structure-property relationships. In aluminum, most experimentally observed grain boundaries deviate significantly from ideal high symmetry structures; however, commonly used GB models are limited to these structures. In this work, an interstitial polyhedral model is used to separate GB structures into bulk and non-bulk (defect) polyhedra. DFT is used to simulate all grain boundary structures which have been experimentally observed in Al, ensuring simulation matches experiment. It has been found that only two defect polyhedra are necessary to describe all experimentally observed boundaries. TEM observation of boundaries in FCC metals is paired with simulation using a defect polyhedral model to explain grain boundary structures. We propose that defect polyhedra determine grain boundary properties, and that the random boundaries of Al are made of the same polyhedra as CSL boundaries, albeit without strict enforcement of periodicity. |
| Proceedings Inclusion? |
Undecided |
| Keywords |
Aluminum, Modeling and Simulation, |