Improved Braking Performance of Cu-Based Brake Pads by Utilizing Cu-Coated SiO₂ Powder

Abstract

The braking performance of copper-based brake pads containing Cu-coated SiO₂ and uncoated SiO₂ was tested on a reduced-scale dynamometer. Results showed that both the stability of the friction coefficient and the wear resistance are improved and the fade phenomenon of the friction coefficient is effectively alleviated during continuous emergency braking (350 km/h, 0.48 MPa) by introducing Cu-coated SiO₂ into the copper-based brake pad. The better braking performance is closely related to the improved interfacial bonding and the firm pinning of SiO₂ particles on the friction surface. The copper coating on SiO₂ reduces the spalling of SiO₂ particles from the copper matrix during the braking process. Therefore, for the sample containing Cu-coated SiO₂, the SiO₂ particles pinned on the friction surface act as trapping sites for wear debris, promoting the formation of secondary plateaus. As a result, the existence of stable primary and secondary plateaus in the braking process promotes the stability of the friction coefficient.

Keywords:

• Copper-based brake pad
• braking performance
• SiO₂
• friction surface

Additional information

Funding

This work was financially supported by the National Key R&D Program of China (2016YFB0301400), National Natural Science Foundation of China (51974029, 51574029), and 111 Project (No. B170003).