Tribological Behavior of Copper and Graphite of Layered Friction Materials

Abstract

Copper and graphite are the main components of copper-based brake materials commonly used in high-speed trains. Their interaction influences the tribological performance of copper-based brake materials. In this article, with copper and graphite as the materials, three kinds of layered samples were prepared as pins and tested against a disc made of H13 steel. Friction tests were conducted under the condition of 0.8–2.35 m/s and pressure of 0.5 MPa using a pin-on-disc tribometer. Results showed that the friction coefficient decreased with an increase in the angle between boundary orientation and the friction direction in the range of 0°–90°. When the angle was 90°, the interaction between copper and graphite was the strongest. Graphite provided positions for friction film accumulation. Copper and its friction film covered and protected the graphite and boundary and reduced the friction coefficient.

Keywords:

• Tribological behavior
• copper
• graphite
• friction coefficient

Additional information

Funding

This work was financially supported by the National Key Research and Development Program of China (No. 2016YFB0301403), Liaoning Natural Science Foundation (No. 20170520374), and the Doctoral Research Start-up Fund of Liaoning Province Science and Technology Department of China (No. 20170520266).