Ag-Cu-MoS2复合材料的真空载流磨损性能

采用粉末冶金方法制备了含有不同Cu质量分数(2%~4%)的Ag-Cu-MoS_2复合材料,并对其力学性能、电学性能和真空载流磨损性能进行了研究.结果表明:较高Cu质量分数的Ag-Cu-MoS_2复合材料表现出较高的硬度和抗弯强度;中等Cu质量分数(2.5%和3%)的Ag-Cu-MoS_2复合材料电刷表现出较低的电压降和电噪声;滑动速度的增加会降低材料间的接触稳定性,进而导致较高的电压降和较大的电噪声.在真空载流条件下与Ag合金盘滑动摩擦过程,不同Cu质量分数的Ag-Cu-MoS_2复合材料电刷均表现出较低的磨损,其磨损率在1×10~(–14)m~3/(N·m)~2.5×10~(–14)m~3/(N·m)范围,其磨损机理主要为疲劳磨损以及黏着磨损.

Wear Performance of Ag-Cu-MoS2 Composites under Current-Loading in Vacuum

Ag-Cu-MoS₂ composites with different weight friction of Cu (2%~4%) were prepared by powder metallurgy. The mechanical performance and vacuum electrical/wear behavior were investigated. The results show that the composites had a higher bending strength and brinell hardness at Cu weight friction of 3.0% to 4.0%, and a lower contact voltage and electrical noise at Cu weight friction of 2.5% to 3.0%. Furthermore, the contact voltage and electrical noise increased as sliding velocity increased. During the sliding against Ag alloy under current-loading in vacuum, all the Ag-Cu-MoS₂ brushes exhibited relatively low wear rates at a range of 1×10^-14~2.5×10^-14 m³/(N·m), and the main wear mechanism was adhesive wear and fatigue wear.