Application of continual annealing and roll bonding (CAR) process for manufacturing Al–Zn multilayered composites

In this study, an aluminium–zinc composite was produced for the first time by using a continual annealing and roll-bonding (CAR) process. A composite with homogeneous distribution of fragmented zinc layers in aluminium matrix was produced after ten CAR cycles. The results demonstrate that tensile strength of the final composites increases up to 410 MPa, which is about 4 times higher than those of initial aluminium and zinc sheets. However, elongation of the composite reduced down to 4% after ten CAR cycles. The fracture surfaces of the tensile samples were observed by scanning electron microscope (SEM) to evaluate the failure mode. Observations reveal that the failure mode in CAR-processed composites is a typical ductile fracture which shows deep dimples in samples with few CAR cycles, while the failure mode was shear ductile fracture with shallow and elongated dimples in samples with ten CAR cycles.

► CAR process was performed on Al–Zn composite.
► Good bonding between layers was achieved by increasing the number of CAR cycles.
► With increasing number of cycles, a good distribution of Zn fragmentations was achieved.
► The composites which were produced by CAR process, possess a higher tensile strength and elongation than ARB process.
► By EDX analysis it is proved that Al and Zn atoms would diffuse with each other.