Robot-based implant resistance welding of carbon fiber reinforced thermoplastics

Kurzfassung

Joining technologies like riveting and bolting, developed for assembly processes of metal structures, are frequently used for joining of carbon fiber composites. Due to the fiber interruptions generated by drilling of holes, the named methods of joining are counterproductive to the idea of optimized carbon fiber composites for high technology lightweight structures. In order to exploit the potential of composite structures, automated, material appropriate joining technologies are inevitable. Automated assembly processes are necessary to manage the increasing production rates and to ensure maximized process stability, reproducibility and traceability. Thermoplastic welding technologies like resistance welding offer high potential for automated, material appropriate joining of carbon fiber reinforced thermoplastics (CFRTP). In this paper the adaption of the resistance welding process to an automated approach for welding of carbon fiber reinforced thermoplastics is demonstrated. Compared to the welding of clips onto a frame or skin structure, clips out of Polyetheretherketone (CF/PEEK) clips are automatically welded onto a CF/PEEK plate. For this use case, an automation system has been developed and its reproducibility and reliability is evaluated.