About this Abstract |
| Meeting |
MS&T26: Materials Science & Technology
|
| Symposium
|
Controlled Synthesis, Processing, and Applications of Structural and Functional Nanomaterials
|
| Presentation Title |
Unusual Dislocation Dynamics in Core-Shell Nanostructures |
| Author(s) |
Robert Fleming |
| On-Site Speaker (Planned) |
Robert Fleming |
| Abstract Scope |
Nanomechanical investigations of Al/a-Si core-shell nanostructures (CSNs) show that these structures have enhanced mechanical properties, including complete recovery of deformation even when loaded beyond the elastic limit. Supporting molecular dynamics (MD) simulations suggest that these materials exhibit unconventional dislocation nucleation and annihilation behaviors, in some cases leading to complete annihilation of nucleated dislocations during unloading. Fundamentally, this mechanical behavior has been attributed to a back-stress that develops in the confined Al core during compression which causes dislocations to retrace their paths or otherwise annihilate upon release, resulting in a return to a completely dislocation-free state in some cases. Knowledge of the physical mechanisms that contribute to the unique mechanical behavior of Al/a-Si CSNs supports an ultimate goal of developing a framework for understanding and controlling dislocation dynamics in confined volumes, which would potentially enable the development of novel functional materials with enhanced mechanical properties. |