The crystallite orientations were measured in high-purity cube-oriented single crystals which had been deformed to 30% by cold rolling. The deformed crystals were sub-divided into macroscopic bands that were parallel to the rolling plane, and into dislocation cells and cell blocks at the microscopic scale. At both scales, crystallite rotations occurred mainly around the transverse direction. A Schmid-factor analysis of plane strain compression revealed that 4 slip systems were active during deformation. The critical slip systems formed 2 co-directional pairs in which the Burgers vector was the same for the 2 systems that comprised a pair. The analysis further revealed that, in a cube-oriented crystal that was subjected to plane strain compression, transverse direction rotations could be produced by a shear amplitude imbalance between the pairs of co-directional critical slip systems. This shear amplitude imbalance did not introduce strain incompatibility. The shear amplitude imbalance which was required in order to produce the observed crystallite rotations at the dislocation-cell scale was found to be equal to about 20% of the average shear amplitude on a single slip system. A model for constructing boundaries, between crystallite pairs, from the dislocations that participated in the deformation process yielded boundaries that exactly accommodated the crystal rotations which were associated with the shear amplitude imbalance between crystallites. In a cube-oriented crystal, this boundary construction process did not limit the orientation of possible boundary planes.

J.A.Wert, Q.Liu, N.Hansen: Acta Materialia, 1997, 45[6], 2565-76