Joining of Anodized and Stacked Aluminum Sheets by Copper Electrodeposition: Nano-Anchor Effect

Abstract

A new manufacturing process for metallic layers is proposed, where no thermal process is required. Al sheets were anodized in H₃PO₄, and the anodized sheets were adhered by Cu electrodeposition. The interface shear strength of Al/Cu was increased significantly from 1.5 to 64.8 MPa by the anodizing. Cu deposition in a small space between the Al sheets was important for the strong adhesion. Microstructural observation showed that Cu deposition penetrated the nanopores of an anodic aluminum oxide (AAO) film, which indicates that the nano-anchor effect played a critical role in the strong adhesion.