Grain Orientation Dependence of Extended Planar Dislocation Boundaries in Cold-Rolled Polycrystalline Aluminium

Abstract:

The dependence on the grain orientation of the alignment of planar dislocation boundaries in plastically deformed metals has been investigated by examining grains of S orientation ({123}<63-4>) in cold-rolled polycrystalline aluminum. For the ideal S orientation the {111} slip plane associated with the highest resolved shear stress lies either at +40° or -40° to the rolling direction in the longitudinal section, with two S variants corresponding to each case. Boundary traces in S orientation grains in the rolled sample were examined by the combined use of electron channeling contrast imaging and electron backscatter diffraction orientation mapping. In each case the +/- sense of the observed planar boundary traces matched that of the {111} slip plane with the highest resolved shear stress showing that the alignment of the boundaries is predominantly controlled by crystallographic rather than macroscopic considerations.

• Periodical: Key Engineering Materials (Volumes 353-358)
• Pages: 711-714
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.353-358.711
• Online since: September 2007
• Authors: Feng Xiang Lin, Andrew Godfrey, Qing Liu
• Keywords: Dislocation Boundaries, Electron Backscatter Diffraction (EBSD), Electron Channeling Contrast (ECC), Grain Orientation Dependence

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