Microstructure evolution and mechanical properties of Cu/Zn multilayer processed by accumulative roll bonding (ARB)

Cu/Zn multilayer was processed by accumulative roll bonding (ARB) up to eight cycles. The evolution of microstructure and its correlation with mechanical properties was investigated. Necking and rupture of constituents were observed at intermediate cycles. The intermetallic CuZn5, microcracks and Kirkendall porosities were formed during ARB. After eight ARB cycles, a laminated composite with wavy interfaces and lenticular fragments of Cu was produced. The maximum tensile strength was achieved after four cycles, which was about 1.4 times higher than that of pure Cu. The hardness of individual layers increased continually with increasing the ARB cycle. Tensile fracture surfaces reveal dimples in both Cu and Zn at early ARB cycles.