The Effect of Sintering Temperature on the Microstructures and Properties of Resin-Bonded Copper–Graphite Brush Materials

Abstract

In this paper, resin-bonded copper–graphite brush materials were prepared by powder metallurgy method with sintering temperatures of 450 °C and 910 °C. The microstructures of both the prepared brush materials and their worn surfaces after current-carrying friction and wear test were characterized. The physical and mechanical properties of the brushes were tested as well. The results indicate that both open pores and MoS2 are the main factors influencing the abrasion resistance of the brushes. The porosity of the brushes sintered at 450 °C is relatively low, and there is a certain amount of MoS2 on the worn surface which provides a self-lubricating effect and reduces the wear during the current-carrying friction and wear process. Brushes sintered at 910 °C have higher porosity which leads to more serious cumulative oxidative wear effects. In the meantime, the MoS2 has decomposed during sintering process, resulting in a relatively poor lubricating effect during friction process.