Characteristics of Electric Signal Transmission according to Relative Amounts of Graphite in Copper-Graphite Brush

Copper-Graphite 브러시 내 흑연의 상대량에 따른 전기 신호 전달 특성에 관한 연구

Electrical and tribological behaviours of a copper-graphite brush in a slipring-brush assembly were investigated to evaluate the characteristics of electric signal transmission between a slipring and a brush. Five brush materials containing different amounts of copper and graphite were studied. The result showed that a copper-graphite brush at a particular graphite content exhibited the most stable frictional and electrical behaviour suggesting an optimum amount of a solid lubricant in a metal-graphite brush system. Microscopic observation and the surface analysis showed good agreements with this phenomena. In addition, the deviation of the friction coefficient and electric signal distortion has a close relationship with a microscopic mechanical vibration and the change of a real contact area.