|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Mechanical Behavior of Nanostructured Materials
||L-157: Anisotropy of Solute Effect on Dislocation Slip in an HCP Metal: A Molecular Simulation Study of Mg Alloys
||Peng Yi, Michael L. Falk
|On-Site Speaker (Planned)
Magnesium has great potential as a lightweight material in transportation and aerospace industries. However, its broad application is limited by poor ductility, originated from its low symmetry HCP structure. Fundamental understanding of the anisotropy of the dislocation slip mechanisms and the associated solute effects is crucial to property prediction and materials design. We studied the mobility of dislocations on the basal, prismatic, and pyramidal planes in Mg/Al and Mg/Y alloys using molecular simulations. Both solute hardening and solute softening were observed and compared favorably with experiments. Solute hardening for in-plane basal slip follows Labusch statistics and Kocks thermo-mechanical model. Solute softening was observed for prismatic slip and pyramidal slip, and it is due to out-of-plane dislocation motions like cross-slip or climb. A 2D energy landscape can be constructed to couple the in-plane and out-of-plane dislocation motions. Lastly, double cross-slip and super-jog formation were observed as potential Frank-Read dislocation multiplication sources.
||Planned: Supplemental Proceedings volume