|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Advanced Characterization Techniques for Quantifying and Modeling Deformation Mechanisms
||Improved Angular and Spatial Resolution of Measured Lattice Rotations in Highly Deformed Bulk Materials through Combining Low-kV EBSD with the Dictionary Indexing Approach
||Ali Gholinia, Timothy Burnett, Bart Winiarski, Farangis Ram, Saransh Singh, Marc De Graef
|On-Site Speaker (Planned)
If the EBSD spatial resolution can be improved, the technique will become superior to TEM analysis for deformation microstructure measurements in that it is fully automated, can measure large areas, and has no sample thickness limitations. Lowering the microscope voltage improves the spatial resolution, but this does not solve the problem of quantifying a highly deformed microstructure; the number of points whose orientations can be determined by the standard Hough-transform analysis decreases from 95% at 20kV to 5% at 5 kV in a shot-peened Al sample. To address this issue, we decrease the capture angle from 90° to 70° and use a dictionary indexing technique which can determine the orientation of 85% of points at 5 kV. We have improved the effective spatial resolution of EBSD, so that details of the deformed microstructure (multi-walled grain and sub-grain boundaries) are revealed that could not be imaged and quantified by EBSD before.
||Planned: Supplemental Proceedings volume