Texture and High-Angle Boundary Formation during Deformation Processing
Among the phenomena leading to formation of high-angle boundaries during deformation processing at low homologous temperatures is the subdivision of prior grains and formation of deformation bands. Evidence for this phenomenon during processing of AA2004, a superplastic aluminum alloy, is reviewed; fragmentation of deformation bands leads to equiaxed grains and high-angle boundaries that support superplasticity. In addition to subdivision, groups of grains undergo lattice rotation toward one or the other variant of the β orientation fibers during plane-strain deformation of pure aluminum by ambient temperature rolling. The formation of equiaxed grains from banded structures during simple shear by equal channel angular pressing (ECAP) is also considered.
Marcello Cabibbo and Stefano Spigarelli
T. R. McNelley et al., "Texture and High-Angle Boundary Formation during Deformation Processing", Materials Science Forum, Vols. 604-605, pp. 251-258, 2009