This work reveals the formation mechanisms of saturation dislocation patterns in three typical multiple-slip oriented [001], [011] and [¯111] copper single crystals. Compared with the single-slip oriented copper single crystals, the three multiple-slip oriented ones show very different dislocation patterns. It was found that the dislocation patterns in cyclically saturated copper single crystals were the Labyrinth structure for [001], wall structure for [011] and cell structure for [¯111], respectively. Based on a two-phase structure consisting of persistent slip bands and veins for single-slip orientation, the formation mechanisms of the dislocation patterns in multiple-slip oriented crystals were proposed as follows: the formation of the complex dislocation patterns depends on the activating slip system. The easy operation of the critical secondary slip system will contribute to the formation of the Labyrinth structure. The activation of the coplanar secondary slip system will be beneficial to formation of the cell structure. If no secondary slip system was activated, the wall structure was more prone to appear. Finally, the intrinsic relationship between various dislocation patterns and face centered cubic crystal structure was established.

Formation Mechanisms of Cyclic Saturation Dislocation Patterns in [001], [011] and [¯111] Copper Single Crystals. P.Li, S.X.Li, Z.G.Wang, Z.F.Zhang: Acta Materialia, 2010, 58[9], 3281-94