Adaptive domain misorientation approach for the EBSD measurement of deformation induced dislocation sub-structures
Pauli Lehto
Abstract
In the current work a novel domain misorientation approach is introduced, which can resolve sub-grains and dislocation cells using conventional EBSD. The measurement principle utilises measurement domains that are grown radially until a specified misorientation value has been reached. This enables stochastic analysis of local misorientation to be carried out within individual sub-grains and dislocation cells. The sub-structural boundaries are classified according to the total misorientation across the boundary region, the thickness of which can vary from approximately one hundred nanometres to several hundred nanometres. Sub-grain boundaries with a total misorientation larger than 2° are resolved effectively for as-measured Hough-based EBSD data. De-noising of the EBSD data allows small dislocation cells to be resolved, typically having a misorientation of 0.4° - 1.0°. The developed approach is applied to various deformed metals, showing a significant increase in the level of detail resolved compared to the conventional kernel misorientation approach. The developed adaptive domain misorientation approach and the EBSD datasets measured for this publication are provided as open access.