| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Mechanical Behavior at the Nanoscale V
|
| Presentation Title |
Nanotwins and Grain Boundaries: Competing Roles on the Nucleation and Propagation of Dislocations Probed via Nanoindentation |
| Author(s) |
Raheleh M Rahimi, Sichuang Xue, Siavash Ghanbari, Xinghang Zhang, David F. Bahr |
| On-Site Speaker (Planned) |
David F. Bahr |
| Abstract Scope |
The influence of grain boundaries on plastic deformation of polycrystalline twinned Al thin films has been investigated using nanoindentation. Arrays of indentations that exhibited elastoplastic pop-ins and grain boundary excursions due to slip transfer were assessed in three textured aluminum thin films. Al (111) shows grain boundary excursions at higher loads, yet has a softer hardness (0.99 GPa), than Al (110) and Al (112) harnesses (1.16 and 1.2 GPa respectively); the (112) film has a very similar grain size as the (111) film and the added strength is attributed to the increased twin density. Molecular dynamics was used to estimate the impact of defects on the onset of plastic deformation in these films. Nanotwins lead to films which deform more uniformly than the more defect free films, and the nanotwins appear to more greatly impact the motion of dislocations rather than the onset or nucleation of dislocations in Al films. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |