Effect of large size graphite on dry friction and wear characteristics of copper-based brake friction lining materials

Abstract

In order to improve the performance of the brake friction lining materials, the materials are made of six powders of Cu-Sn-Fe-graphite-SiO2-MoS2. The graphite content is 6%, 8%, 10%, 12% and 15% respectively. The size of graphite is 400-600μm. The dry grinding wear properties are investigated. The results show that the compressive strength decreases as the graphite content increasing. When the content is 10%, the strength is 113.45MPa; it satisfies the performance requirements of high-iron brake pads. The dry friction and wear test of a copper-based friction material containing a large graphite sheet shows that the wear resistance is affected by the graphite contents. When the graphite content is 10%, the wear rate is significantly lower than other contents; the wear resistance is the best. During the wear process, a variety of wear mechanisms coexist. Such as oxidation wear, abrasive wear, adhesive wear, and peeling wear. At low speeds, the main wear mechanisms are abrasive and oxidation wear. At high speeds, the main wear mechanisms are oxidation wear and peeling wear.