压力对碳纳米管-银-石墨复合材料接触电压降的影响  

Effect of Pressure on the Contact Voltage Drop of CNT-Ag-G Composite

作　　者：凤仪[1] 张敏[1] 徐屹[1] 

机构地区：[1]合肥工业大学材料科学与工程学院,安徽合肥230009

出　　处：《金属功能材料》2005年第4期11-14,共4页Metallic Functional Materials

基　　金：国家自然科学基金(50271021);安徽省自然科学基金(03044601);日本NSGF基金项目。

摘　　要：采用粉末冶金法制备碳纳米管-银-石墨复合材料电接触材料,在带电状态下(10A/cm2),研究了压力对碳纳米管-银-石墨复合材料接触电压降的影响,结果表明:当压力较小时(10N/cm2,5N/cm2),由于电刷的跳动产生火花,导致复合材料接触电压降较大;随压力增加,复合材料电刷和换向器的实际接触面积增大,接触电阻减小,电刷的接触电压降下降;由于碳纳米管的研磨作用,阻止了润滑膜随磨损时间延长而增厚,使电刷的接触电压降维持在一个较稳定的数值上。CNT-Ag-G composite brushes were fabricated by means of powder metallurgy. Under 10A/cm^2 and different pressure（SN/cm^2 -30N/cm^2） conditions, the contact voltage drop of CNT-Ag-G composite brushes was studied and worn surface was observed using SEM. The results show：when pressure is small （10N/cm^2 ,5N/cm^2） ,because of the increase in the roughness and intensification of the abrasive properties of the metal counterbody surface, the contact voltage drop of CNT-Ag-G composite is bigger;with the increase of pressure, the contact area between brush and commutator increases and the contact resistance decreases and leads to the decrease of contact voltage drop. Due to the polishing of CNT, the lubricating film doesn＇t thicken and contact voltage drop of composite remains constant with the increase of weartime.

关 键 词：碳纳米管-银-石墨复合材料 电接触材料 接触电压降 压力 粉末冶金 

分 类 号：TB332[一般工业技术—材料科学与工程]