Microstructural development and its effects on mechanical properties of Al/Cu laminated composite

The microstructural development and its effect on the mechanical properties of Al/Cu laminated composite produced by asymmetrical roll bonding and annealing were studied. The composite characterizations were conducted by transmission electron microscope (TEM), scanning electron microscope (SEM), peeling tests and tensile tests. It is found that the ultra-fine grained laminated composites with tight bonding interface are prepared by the roll bonding technique. The annealing prompts the atomic diffusion in the interface between dissimilar matrixes, and even causes the formation of intermetallic compounds. The interfacial bonding strength increases to the maximum value owing to the interfacial solution strengthening at 300 degrees C annealing, but sharply decreases by the damage effect of intermetallic compounds at elevated temperatures. The composites obtain high tensile strength due to the Al crystallization grains and Cu twins at 300 degrees C. At 350 degrees C annealing, however, the composites get high elongation by the interfacial interlayer with submicron thickness.