The stress-strain curve of twisted Cu rods, pre-deformed by axial shaping, presented in its initial part the strain softening range followed by the strain hardening range. In the strain softening range, the smaller density of dislocations in the interior of grains and the smaller width of the grain boundaries were observed as a result of the redistribution of dislocations due to activation of different slip systems. In the strain hardening range, the high dislocation density was noted in the interior of particular grains as well as near the grain boundaries which was characteristic for the pre-deformed state. Thus the rearrangement of dislocation distribution, leading mostly, to the diminution of dislocation density in the interior of crystallites, seems to contribute to the work softening in that transient range. (C) 2003 Elsevier Science B.V. All rights reserved.