About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advanced Characterization Techniques for Quantifying and Modeling Deformation
|
| Presentation Title |
G-4: Measuring and Modeling Geometrically Necessary Dislocation Densities in Magnesium Alloys Using EBSD and PRISMS-Plasticity |
| Author(s) |
Michael Pilipchuk, Tracy Berman, Eunji Song, Amit Misra, John Allison, Veera Sundararaghavan |
| On-Site Speaker (Planned) |
Michael Pilipchuk |
| Abstract Scope |
Strain gradients in polycrystals lead to the formation of geometrically necessary dislocations (GNDs) to maintain compatibility. During deformation, these dislocations naturally accumulate near grain boundaries to accommodate lattice rotations, creating a heterogeneous density map. As the sample’s GND densities increase, dislocation interactions increase, and hardening is observed. Thus, to improve simulations, GND density calculations have been added to the PRISMS-Plasticity crystal plasticity finite element code. These use the Nye tensor rate, from the curl of the plastic deformation gradient and the rate of shear on each slip system, which is then decomposed onto the slip systems.
Previous experiments found GND densities using electron backscatter diffraction maps of ZX30 (Mg–3Zn–0.1Ca by wt%) deformed at 200ºC in plane strain compression and Mg-4Al under tension. In this computational work, EBSD data and DREAM.3D are utilized to recreate experimental microstructures and compare GND density distributions between the experimental and computational results |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, Characterization, |