Mechanical properties optimization and microstructures of diffusion bonded AA2014/AA7075 al alloys

Diffusion bonding has been successfully used to join dissimilar high-strength aluminium alloys. In bonding AA2014 with AA7075 aluminium alloy, the main diffusion bonding process parameters were optimized to achieve optimum shear and ram tensile strengths. For the strategical planning of experiments, the design of experiment concept was used, as well as the response surface methodology to create statistical models for optimizing the process parameters. The bond strength improved as the interface thickness increased, but above 6 µm (at about 375 °C), the bond strength began to deteriorate. Similarly, the stiffness of the joint interface increased as the process temperature increased due to the development of interfacial phases. The empirical findings were evaluated, and the optimal bonding range was determined in order to maximize the bond’s shear and ram tensile strength.