Copper plays an important role in brake pads. For example, copper is frequently said to have a wear-inhibiting effect. At the same time, copper particles released from brake pads have a negative impact on the environment if they enter the groundwater. For this reason, efforts are being made to substitute copper in brake linings as far as possible. In cooperation with Volkswagen AG, brake pads with different copper contents (powder) are investigated in this work, focusing specifically on their wear behaviour on a pin-on-disc tribometer. The tribometer, which is available at the Institute for Dynamics and Vibrations at the Technical University of Braunschweig, is fully automat-ed and has high-precision laser measurement technology that is specially optimized for wear analysis. In principle, this allows high-precision surface measurement after every friction application. In addition, the tribometer is equipped with a heating box, which allows measurements with disc and pad temperatures of up to 200°C. This paper systematically investigates how the copper content in brake pads controls wear in the short and long term. Like observations in the literature, the results show that no general statements can be made regarding the influence of the copper powder content on wear behaviour and that the shape of the copper as well as the interactions of copper with other brake pad com-ponents seem to play a significant role.

TU Braunschweig: Mr. Jacek Kijanski, Prof. Dr.-Ing. Georg-Peter Ostermeyer; Volkswagen AG: Mr. Niels Wächter, Dr.-Ing. Aaron Völpel, Mr. Florian Guckeisen