Effects of asymmetrical roll bonding on microstructure, chemical phases and property of copper/aluminum clad sheet

Abstract

The present paper investigated the morphology and chemical phases of interfacial layer of Copper/Aluminum clad sheet by scanning electrical microscope equipped with energy dispersive X-ray detector and X-ray diffraction, also measured the mechanical property through micro-hardness test. The results are that the interfacial bonding is enhanced and the thickness of interfacial layer increases with mismatch speed ratio rising. The improved interfacial bonding can be found from the tensile fracture. The formation of intermetallic compound (IMC) is promoted by the significant element diffusion at high speed ratio. For sample annealed at 400 °C for 20 min, the formation of IMC is negligible, but the fracture lies between compounds. The micro-hardness on the interface decreases with speed ratio increasing. The study shows that the improvement of microstructure and mechanical property and formation control of IMC of Copper/Aluminum clad sheet can be achieved using asymmetrical roll bonding with high speed ratio.