Microstructure/mechanical properties relationship in electrodeposited Ni/Cu nanolaminates

Laminated Ni/Cu structures were made by electrodeposition using a single ba th sulfamate solution. The texture of deposits was Found to depend on their thickness, purity of the electrolyte and its copper content, deposition te mperature, and the bi-layer thickness. The deformation and fracture of thes e structures were characterized by testing free-standing tensile specimens. The fracture behavior varied drastically among the specimens - from so-cal led knife-edge behavior to complete cleavage-like fracture. The purity of t he solution and nodule formation was found to be the most important factors that affected the ductility of the deposits. The observations made in this study suggest that co-deposition of hydrogen is responsible for the embrit tlement of specimens produced from impure electrolytes. (C) 2001 Elsevier S cience B.V. All rights reserved.