Strain softening effects in texture and microstructure of torsioned pre-deformed Al rods

Abstract

Abstract The strain softening effect is exemplified on Al rods (99.8 wt.% purity) torsioned after pre-deformation by rolling, where that effect is most distinct. Observations of thin foils in Al rods, parallel to cross – sectional plane as well as along longitudinal section, were carried out on samples deformed up to the shear deformation φ = 0.645, i. e., near the end of the stress softening range, and on samples deformed up to the shear deformation φ = 5.193, i.e., near the maximum of the strain hardening range. In the strain softening range we have noted: (a) a decrease in dislocation density in the grain interior and in the grain boundary, and (b) formation of a strong (001)[110] shear texture component. Growing dislocation density and formation of axial 〈111〉+〈100〉 texture components were observed during torsion in the strain hardening range.