An Investigation on Microstructures and Mechanical Properties of Ultra-Low Cu Layer Thickness Ratio Cu/8011/1060 Clads

High-performance, ultra-low Cu layer thickness ratio pure Cu/8011 Al alloy/1060 Al alloy (Cu/8011/1060, for short) clads were first fabricated by roll casting and then roll bonding. The effects of rolling reduction rates on the microstructural evolutions and mechanical properties of Cu/8011/1060 clads during the roll-bonding process have been systematically investigated. Results show that the continuous but unequal-thickness intermetallic compound (IMC) layer is fractured after roll bonding. The fracture location is mainly at the transition zone between type I and type II IMCs or in the interiors of type I and type II IMCs. The IMCs are identified as Al 4 Cu 9 , AlCu and Al 2 Cu. The Cu layer thickness ratio decreases from 13.7 to 4.1 pct after roll bonding. The Cu/8011/1060 clads prepared at the rolling reduction rate of 47 pct have the best comprehensive mechanical performance with an ultimate tensile strength (UTS) of 135.7 MPa and elongation (EL) of 25.5 pct. Two different tensile fracture modes are observed for Cu/8011/1060 clads fabricated at different rolling reduction rates.