Recrystallization Texture of Copper as a Function of Layer Thickness in Roll-Bonded Cu-Nb Composites

摘要

The extraordinary strength values of composites with nano-scale layers or phases have inspired much investigation into the strengthening mechanisms of laminated composites such as Cu-Nb. The annealed microstructure and texture of any material govern its mechanical properties in composites just as much as in single-phase materials yet studies on the development of annealing textures of such deformed layered composites are still very limited as compared to studies of strengthening mechanisms. Recrystallization textures of monolithic pure Cu and alloyed Cu -C19210 as well as when they are reinforced with Nb using roll-bonding are investigated. The roll-bonded samples of different layered length scales were deformed to reductions of 70-90% and annealed at 300℃ and 800℃ for 0.5 hours. We found that the Cube and R-orientation {124} < 211 > were the dominant components in the recrystallized texture of monolithic pure Cu and alloyed Cu respectively. However, retained rolling texture was obtained for the sub-micron Cu layers of the composites. X-ray analysis and EBSD was used to study the recrystallization evolution of the Cu in the composites. EBSD in particular was also used to observe recrystallization for the sub-micron Cu layers. In this paper we also discuss the effect of the length scale of the Cu layer thickness on the recrystallized texture especially in the sub-micron range.