Abstract

The objective of this research was to study the evolution of crystallographic texture in electrodeposited Ni/Cu laminated nanostructures. Thick films consisting of nickel and copper nanolayers were fabricated on annealed polycrystalline copper substrates using an electodeposition technique. The microstructure of the deposits was varied by changing the deposition time of each layer and the electrolyte temperature. X-ray diffraction, transmission electron microscopy and scanning electron microscopy were applied to characterize the deposits. Three microstructural behaviours were observed. The deposit with a very fine bilayer thickness was composed of coherent layers parallel to the substrate surface. This deposit replicated the cube orientation of the substrate and showed a strong d 100 ¢ texture throughout the thickness of the deposit. An increase in the bilayer thickness caused a change in the texture from d 100 ¢ on the substrate side to d 111 ¢ on the solution side. This change in texture is suggested to be associated with a change in the deposition front orientation from d 100 ¢ to d 110 ¢ and the subsequent twinning of the cube-oriented crystals. A decrease in the electrolyte temperature inhibited faceting of the interface and hence no twinning was observed