Space-Saving Joining Technique
Hybrid parts combine the properties of plastics and metals. Combinations of carbon fiber-reinforced plastics (CFP) and aluminum are frequently joined by means of adhesive or mechanical methods. For instance, in the automobile industry a method that combines riveting and adhesive bonding is used in many cases to assemble CFP vehicle bodies to the aluminum vehicle frame.
Scientists at the Fraunhofer Institute for Manufacturing Technology and Advanced Materials have now developed novel approaches for solving the problem of how to join aluminum and CFP. These involve placing a transition structure between the materials to be joined. These transition structures may be based on glass fibers or titanium and can be incorporated directly into the aluminum components by means of aluminum casting. Compared to conventional joining techniques, this transition from metal to fiber-reinforced composite reduces the size and weight of the part. In addition, the incorporated joining element isolates the materials electrically. This improves the corrosion characteristics of the composite part consisting of aluminum and CFP.
The new joining technique could lead to weight-optimized, integral structures with improved mechanical properties. Besides the automobile industry, hybrid parts made from aluminum and CFP find use in the aircraft industry, wind turbines and in machinery construction.