Effect of Annealing Process on Mechanical and Microstructural Properties of Al6061/Cu and Al/6063/Cu Cladding Materials Fabricated by the Caliber-Rolling Process

Al6061/Cu and Al6063/Cu cladding materials have been produced by the caliber-rolling process at 298 K. The prepared specimen was post-annealed at a temperature of 773 K for various time durations, and the effects of annealing conditions have been investigated. Vickers hardness of Al6061, Al6063 and Cu decreases as annealing time decreases; however, that of the interface between Al alloys and Cu increases with an annealing time of 1 h, and then decreases as annealing time increases further. The growth of a diffusion layer in Al6063/Cu is larger than that in Al6061/Cu, because the activation energy in the Al6063/Cu is lower than that in Al6061/Cu during the annealing process. Cracking of the diffusion layer occurs by annealing for extended periods of time in both materials, which contributes to the decrease in hardness.