| About this Abstract |
| Meeting |
2022 TMS Annual Meeting & Exhibition
|
| Symposium
|
Grain Boundaries and Interfaces: Metastability, Disorder, and Non-Equilibrium Behavior
|
| Presentation Title |
Grain Boundary Pop-in during Nanoindentation of W: Recent Observation on Dislocation Grain Boundary Interaction |
| Author(s) |
Karsten Durst |
| On-Site Speaker (Planned) |
Karsten Durst |
| Abstract Scope |
Nanoindentations were performed in the vicinity of grain boundaries (GBs) in polycrystalline tungsten, observing in some cases a secondary grain boundary pop-in in the load–displacement curve. The dislocation microstructure in the plastic zone of the residual impression was analysed using sequential polishing, electron channelling contrast imaging (ECCI) and electron backscatter diffraction (EBSD) analysis on and below the surface. A significant hardness increase was observed before the GB pop-in event. The careful ECCI analysis on polished cross sections shows the dislocation pile-up in the vicinity of the GB along with transmitted dislocations in the adjacent grain. For some indentations, the interaction of the dislocations within the plastic zone and the GB leads to a localized GB movement on or below the surface. The occurrence and magnitude of GB movement are found to be strongly influenced by misorientation between the adjacent grains, the orientation and distance of the indenter to the GB. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Mechanical Properties, Other, Other |