Rapid Electron Backscatter Diffraction Mapping: Painting by Numbers

TL;DR

Rapid EBSD combines FSE imaging with sparse EBSD sampling to quickly map microstructures, significantly reducing analysis time while maintaining detailed phase and orientation information.

Contribution

This work introduces a novel data fusion method that accelerates microstructure characterization by integrating FSE imaging with sparse EBSD sampling.

Findings

Effective microstructure mapping in cobalt superalloy and titanium alloy

Significant reduction in analysis time compared to conventional EBSD

Maintains accuracy in phase and orientation identification

Abstract

Microstructure characterisation has been greatly enhanced through the use of electron backscatter diffraction (EBSD), where rich maps are generated through analysis of the crystal phase and orientation in the scanning electron microscope (SEM). Conventional EBSD analysis involves raster scanning of the electron beam and the serial analysis of each diffraction pattern in turn. For grain shape, crystallographic texture, and microstructure analysis this can be inefficient. In this work, we present Rapid EBSD, a data fusion approach combining forescatter electron (FSE) imaging with static sparse sampling of EBSD patterns. We segment the FSE image into regions of similar colour (i.e. phase and crystal orientation) and then collect representative EBSD data for each segmented region. This enables microstructural assessment to be performed at the spatial resolution of the (fast) FSE imaging whilst including orientation and phase information from EBSD analysis of representative points. We demonstrate the Rapid EBSD technique on samples of a cobalt based superalloy and a strained dual phase titanium alloy, comparing the results with conventional analysis. Rapid EBSD is advantageous for assessing grain size distributions in time-limited experiments.