The wear of brake pads is investigated from the aspect of dissipated energy during friction for disc brake systems, using the IDS-high load tribometer and the device of contactless wear measurement. Based on the adhesion theory of friction and its extensions, the ratio of wear and dissipated energy indicating the wear resistance of brake pads is derived as a piecewise defined function. The new derivate wear model demonstrates in physics mechanisms between the wear and the dissipated energy during different friction processes. It is also used to preliminarily evaluate the wear resistances of brake pads under different friction scenarios, even without tribometer friction tests. Thus, the wear formula can provide some theoretical guidance for manufactures and quality inspections of brake pads. Results of tests are well presented to illustrate different linear correlations between wear of brake pads and dissipated energy, under various levels of normal loads without reaching high temperatures. In the tests, it is also discovered that the real contact condition is a key towards exactly resolving quantized questions for wear of brake pads during braking. These test results can be adequately interpreted by the new wear model.
Ren Haichuan, Georg-Peter Stermeyer - Institute of Dynamics and Vibrations