About this Abstract |
Meeting |
2021 TMS Annual Meeting & Exhibition
|
Symposium
|
Advanced Characterization Techniques for Quantifying and Modeling Deformation
|
Presentation Title |
Dislocation Imaging by Precession Electron Diffraction |
Author(s) |
Dexin Zhao, Kelvin Xie |
On-Site Speaker (Planned) |
Dexin Zhao |
Abstract Scope |
Dislocation imaging is usually done by regular bright-field imaging in the transmission electron microscope (TEM) under the two-beam or low-index zone axis (multiple-beam) conditions. However, both techniques have drawbacks. Two-beam condition limits the holistic illumination of dislocations. Regarding the low-index zone axis imaging, more dislocations could be illustrated, but the dynamical effect usually overwhelms the contrast from the dislocation lines. In this work, we employed precession electron diffraction (PED) as a tool for dislocation imaging using deformed AZ31 as a model material. The beam precession could also be utilized to potentially generate high-quality micrographs with enhanced dislocation contrast. One major result of beam precession is to average out the dynamical effect in TEM micrographs and to show high-quality kinematical information. We demonstrated PED is a powerful characterization technique that could remove the dynamical effect and better reveal dislocations under the multiple-beam conditions. |
Proceedings Inclusion? |
Planned: |
Keywords |
Characterization, Magnesium, |