EBSD Analysis of Orientation Gradients Developed near Grain Boundaries

Abstract

The local misorientation and orientation gradient development near grain boundaries (GBs) are analyzed in a deep drawing quality steel sheet (AKDQ) subjected to interrupted tensile tests in a notched sample. The microstructure is studied using electron backscatter diffraction (EBSD) with subgrain-level spatial resolution. The evolution of misorientation accumulation for particular GBs was traced in grains located in different zones inside the notch, identifying the effective area of influence of GBs inside the neighboring grains. A local study was performed, and the evolution in misorientation development near GB was investigated. The results show a low correlation between GB width and sharpness of the orientation gradient with the mesoscopic strain, but instead orientation gradients between GB zones and the interior of the grains were observed with increasing strain. The increase in severity observed in some GBs can be related to dislocation pile up development, which reduces the permeability of a boundary to dislocation transmission.

Patterns of Grain Fragmentation During Plastic Deformation of Metals at Small to Medium Strains (Brief Review)

“…Note that before appearance of distinct fragments, orientation gradients in regions, which sizes significantly exceed the mean size of cell block, appear from the very beginning of deformation [60][61][62][63][64]. It has been detected that misorientation decreased linearly from the grain boundary into the inner part of the grain in interstitial-free steel [60] and copper [63] subjected to uniaxial tension.…”

Preparation and properties of artificial bone with lead-free piezoelectric materials

“…As is known, the lead-free BT phase possesses great piezoelectric properties, which would be beneficial to the biological properties enhancement of HA based materials. [30][31][32] Thus, it is highly expected that the BT/HA ceramics would have great biological performance. According to the SEM images shown in Fig.…”

Neighbor-Affected Orientation Rotation in the Grain Boundary Region

“…Subedi et al [ 18 ] and Wright et al [ 19 ] described the magnitude of orientation subdivision near a grain boundary by kernel average misorientation (KAM) and grain reference orientation deviation (GROD) based on EBSD. Signorelli et al [ 20 ] and De Vincentis et al [ 21 ] presented the width and sharpness of orientation gradient near a grain boundary by gradient average severity (GAS) and boundary effective thickness (BET). In addition, Nagarajan et al [ 22 ] proposed that grain tends to rotate towards the neighboring orientation with the smallest misorientation angle, and this rotation tendency fails when the misorientation angle is greater than 30°.…”