Effect of Annealing on the Interface and Microstructural Properties of Al/Cu Composites Processed by Hot Pressing and Subsequent Cold Rolling

Considering the significance of understanding the mechanism of intermetallic compounds formation in Al/Cu composites, in this research, Al/Cu layered composites were processed by hot pressing, cold rolling and then were annealed at temperatures of 300-500 degrees C for 30-360 min. The Al/Cu interface characteristics, microstructural evaluation, deposits growth behavior and mechanical properties of Al/Cu composites after pressing, rolling and heat treatment have been determined using OM, SEM, EDS, XRD and UTM. The results show that after annealing, intermetallic particles formed during hot press are not growing anymore, but new intermetallic layer begins to nucleate and grow at Al/Cu bonded area and form a new intermetallic layer, and the growth components are 0.56, 0.49 and 0.46 at 300, 400 and 500 degrees C, respectively. The growth components are good approximations that indicate that the growth of the intermetallic layer is controlled by volume diffusion. Also, the stress-strain curve consists of five distinctive areas due to the nature of deformation of two metals.