Electron back scatter diffraction (EBSD) has made an impressive impact on the characterization of materials by directly linking microstructure and crystallographic texture to provide very rich and quantitative datasets which in many instances have forced us to rethink how microstructure should be defined and analyzed. In this article we try to first give a very basic idea of how an EBSD map is obtained and what the data produced is like. We then give a brief history detailing some of the more major steps in developing the technique to what it is today. Finally, we explore two advanced and exciting technique areas of strain mapping and 3D microscopy and demonstrate how the EBSD technique continues to evolve to tackle new applications and bolster our materials characterization toolbox. © 2012 Elsevier Ltd

The deformation around a 500-nm deep Berkovich indent in a large grained Fe sample has been studied using high resolution electron back scatter diffraction (EBSD). EBSD patterns were obtained in a two-dimensional map around the indent on the free surface. A cross-correlation-based analysis of small shifts in many sub-regions of the EBSD patterns was used to determine the variation of elastic strain and lattice rotations across the map at a sensitivity of ∼±10⁻⁴. Elastic strains were smaller than lattice rotations, with radial strains found to be compressive and hoop strains tensile as expected. Several analyses based on Nye's dislocation tensor were used to estimate the distribution of geometrically necessary dislocations (GNDs) around the indent. The results obtained using different assumed dislocation geometries, optimisation routines and different contributions from the measured lattice rotation and strain fields are compared. Our favoured approach is to seek a combination of GND types which support the six measurable (of a possible nine) gradients of the lattice rotations after correction for the 10 measurable elastic strain gradients, and minimise the total GND line energy using an L¹ optimisation method. A lower bound estimate for the noise on the GND density determination is ∼±10¹² m⁻² for a 200-nm step size, and near the indent densities as high as 10¹⁵ m⁻² were measured. For comparison, a Hough-based analysis of the EBSD patterns has a much higher noise level of ∼±10¹⁴m⁻² for the GND density.