The Copper aluminum roll bonded clad plate developed by Henan Chalco is an effective process for producing copper-aluminium roll bonded sheets. It can overcome the large difference of properties between copper and aluminium and achieve solid metallurgical bonding at the interface.
Before rolling, the surface of aluminium and copper should be cleaned up and roughened. The common method is rotating steel brush method, which produces a brittle coating on the metal surface through the work hardening of the steel brush. In addition, a certain roughness of the joint surface is also obtained.
During rolling, copper and aluminium are extruded and embedded into each other, physicochemical action occurs, and preliminary composite is achieved. With rolling, the embedded metal begins to expand and extend, forming a large area of embedded, achieving the desired composite effect.
In the subsequent diffusion annealing process, under the action of high temperature, the metal atoms on the interface get enough energy to diffuse with each other, eliminate the defects, eliminate the internal residual stress, and form a certain depth of diffusion layer on both sides, so as to achieve the desired composite effect.
