Qualities of electron backscatter diffraction patterns and image contrast from a ferritic-martensitic steel microstructure

Abstract

Quality metrics of electron backscatter diffraction patterns were constituted with a few descriptors of the characteristic intensity distribution across diffraction bands. The image contrast by these metrics was compared quantitatively with a ferritic-martensitic dual phase steel. The metrics which described the sharpness of bands were superior to those that represented the contrast from a background intensity. In addition, the ones that were defined around the edges of a band presented better contrast than those in the interior. Pattern degradation by martensite was approximated with lattice rotations in an interaction volume, and the sensitivity of the metrics to pattern degradation accords well with their behavior on the experimental patterns. The metrics defined around the band edges were more prone to instability in the evaluation processes. A new metric which described the sharpness in the interior of bands presented a compromise between the sensitivity and the stability. • Pattern quality metrics of EBSD were compared with a ferritic-martensitic steel. • Metrics by band sharpness presented higher-contrast micrographs than by contrast. • The edges of a band gave better contrast but poorer stability than the interior. • A metric of sharpness in a band interior presented an excellent compromise.