Size effect on texture of multiscale Cu in CuNb nanocomposite wires

CuNb nanocomposite wires prepared by accumulative drawing and bundling (ADB) exhibit multiscale microstructures: the size of Cu ranges from micrometer to nanometer, and Nb is nano-scale. In this work, Electron backscattering diffraction (EBSD) and precession electron diffraction (PED) are used to characterize the textures of micron−/submicron-scale and nano-scale Cu (Nb), respectively. The results indicate that the texture of Cu at different size scales varies significantly. Micron- and submicron-scale Cu shows noticeable texture gradients along the radial direction of wires, whereas nano-scale Cu and Nb fibers have homogeneously distributed textures. Micron-scale Cu has a 〈111〉 texture in wire center region and a random texture in edge; submicron-scale Cu develops a strong 〈100〉 texture in center and a < 111> texture in edge region; nano-scale Cu and Nb fibers exhibit strong 〈111〉 and 〈110〉 textures throughout the wire, respectively. Dynamic recrystallization during deformation leads to weakening of the texture strength in micron-scale Cu, while almost negligible effects on the texture of submicron- and nano-scale Cu/Nb due to the size and interface effects.