Growth of Intermetallic Phases in Al/Cu Composites at Various Annealing Temperatures During the ARB Process

The purpose of this study is to discuss the effect of annealing temperatures on growth of intermetallic phases in Al/Cu composites during the accumulative roll bonding (ARB) process. Pure Al (AA1100) and pure Cu (C11000) were stacked into layered structures at 8 cycles as annealed at 300 degrees C and 400 degrees C using the ARB technique. Microstructural results indicate that the necking of layered structures occur after 300 degrees C annealing. Intermetallic phases grow and form a smashed morphology of Al and Cu when annealed at 400 degrees C. From the XRD and EDS analysis results, the intermetallic phases of Al2Cu (theta) and Al4Cu9 (gamma(2)) formed over 6 cycles and the AlCu (eta(2)) precipitated at 8 cycles after 300 degrees C annealing. Three phases (Al2Cu (theta), Al4Cu9 (gamma(2)), and AlCu (eta(2))) were formed over 2 cycles after 400 degrees C annealing.