The role of shear banding on deformation texture in low stacking fault energy metals as characterized on model Ag crystals Original Research Article

The microstructure and texture evolution during deformation of a representative low-stacking fault energy (SFE) metal was characterized by detailed local scanning electron microscopy and transmission electron microscopy orientation measurements. High purity silver single crystals with an initial (1 1 2)image orientation were channel die deformed to total reductions of 88% (logarithmic strains 2.1), first developing twin-matrix layers and then compact clusters of two families of shear bands. It was shown that twinning and shear banding caused several important transitions of the deformation textures. The as-deformed shear bands exhibited large orientation spreads of up to 40° with respect to the adjacent twinned areas. Most of these misorientations occurred by rotations about the transverse direction ∥〈1 1 0〉 axis with significant further rotations about 〈1 1 2〉 poles. These two rotations explained the influence of the shear bands on the formation of Goss{1 1 0}〈0 0 1〉 and brass{1 1 0}〈1 1 2〉-S{1 2 3}〈6 3 4〉 texture components, which are clearly observed in highly deformed low-SFE metals. Symmetrically equivalent crystal lattice rotations inside narrow areas led to the formation of the positive and negative macroscopic shear bands for high deformations.