Lightweight Chassis Components — The Development of a Hybrid Automotive Control Arm from Design to Manufacture

In this work, the development of a hybrid lightweight automotive chassis control arm is demonstrated. It includes the development of a new simulation method for designing metal — LFT (long fiber-reinforced thermoplastics) rehybrid parts and the new hybrid forming method for its manufacture. Beginning with the original geometry of a series steel chassis control arm, the design was optimized for the hybrid forming process where a steel sheet part is reinforced by an LFT rib structure, and both parts are joined by an LFT layer. For this purpose, a new FE optimization process chain was established. The thickness of the sheet metal and LFT layers, the geometry and thickness of the ribs of the hybrid control arm could be determined to meet both mechanical and light weight requirements. Afterwards, a suitable tooling concept and process for the hybrid forming were developed and tested. The forming behavior of two different steel grades along with an LFT was demonstrated and analyzed with the help of 3D measurement techniques and relevant section cuts. Finally, a weight reduction of nearly 20 % compared to the original component was realized with the hybrid forming process.