Abstract: The symmetrical and asymmetrical rolling process was used to produce Cu/Al composite strip. Interfacial reaction during annealing and strengthening mechanism after asymmetrical rolling were investigated. The interfacial microstructure and fracture morphology of tensile test were obtained by scanning electrical microscope. The distribution of interfacial elements was analyzed by line scanning and electron microprobe analysis. The interfacial phases were analyzed by XRD. The peeling and tensile tests were carried out to study mechanical properties of the composite strips. The results indicate that the diffusion layer with three sublayers forms after annealed at 400℃ for 1h. There is a sudden change of element content in each sublayer. A large amount of copper and the CuAl₂， Cu₉Al₄， CuAl and Cu₄Al phases are detected on the Al peeled surface， while only the Cu₉Al₄ and Cu₄Al phases are detected on the Cu peeled one. Therefore， the asymmetrical rolling bonding can improve the interfacial strength and tensile property of the composite strip and reduce the damage of interfacial interlayer from the failure.

Key words: Cu/Al composite strip, asymmetrical rolling, annealing, interface, intermetallic compound