The features of the deformation bands in Cu single crystals under cyclic straining were surveyed. A simple model was proposed to account for the formation of deformation bands. In this model, both crystal rotation and dislocation density variation induced by cyclic straining were considered. The gradual lattice rotation caused by tension and compression irreversibility was the main driving force for the formation of deformation bands. The drastic release of mobile dislocations resisted by the primary slip bands was the direct trigger for the formation of deformation               bands. From               this analysis,               one may 

understand why the formation of deformation bands was easier in Cu single crystals with double- and multiple-slip orientations than that with single-slip orientation.

On the Formation of Deformation Bands in Fatigued Copper Single Crystals. S.X.Li, X.W.Li, Z.F.Zhang, Z.G.Wang: Philosophical Magazine A, 2002, 82[16], 3129-47