Measuring the Plastic Zone Size by Orientation Gradient Mapping (OGM) and Electron Channeling Contrast Imaging (ECCI)

Abstract For the local investigation of plastic deformation mechanisms non‐destructive methods are needed to image the distribution of dislocations and to measure dislocation densities. Additionally these methods should be usable in situ. Therefore the well known methods EBSD and ECCI are improved by an appropriate processing of the measured data. The resulting two new techniques OGM and ECCI‐plus are validated in detail for two complex sets of experiments. Both techniques are used to image plastic deformation zones and to measure the size of plastic zones on a macro scale (hardness indents) as well as on a micro scale (crack tips) as demonstrated in this paper. Additionally OGM gives even quantitative data of the degree of deformation. The capability of both methods is discussed in detail and it is shown that they are independent from the topography which is critically surveyed.