Rolling process and properties of copper cladding aluminum flat bars using continuous casting bars with the rectangle section

Copper cladding aluminum (CCA) rods with the section dimensions of 50 mm × 30 mm × 3 mm × R4 mm were fabricated by horizontal core-filling continuous casting (HCFC) technology, and then CCA flat bars with the section dimensions of 60 mm × 8 mm were formed from the CCA rods by multi-pass rolling and finishing drawing process. The reasonable rolling process, mechanical properties and electrical properties of the flat bars were investigated subsequently. The results confirm the correlation between the width of the flat bars after rolling and the side-edge cracking behavior. The width of the flat bars can be controlled by allocating the pass reduction and setting the temperature of the rolling process, thereby suppressing the side-edge cracking in the flat bars. The reasonable rolling temperature range is from room temperature to 200℃. When rolling at room temperature, the much reasonable rolling schedule is 5 passes flat rolling, the 1st pass reduction of about 20% and the highest pass reduction of about 30%. Through 1 pass finishing drawing after the rolling process, the flat bars can be obtained with precise section size and excellent surface quality. After annealing treatment, the electrical resistivity of the flat bar is 2.084 × 10^-8 Ω·m, the tensile strength is 122.7 MPa, the elongation is 22.0% and the shear bonding strength of the interface is 25.9 MPa.