Friction and wear behaviors of two friction couples,the pure carbon/copper alloy contact wire and the metalimpregnated carbon/copper alloy contact wire were studied experimentally on a ringonblock friction wear tester under different vibration amplitudes.The test results indicate that an approximate sinusoidal vibration of the strip occurs continuously.The arc discharge power consumption of two friction couples is firstly increased and then decreased with the increasing of vibration amplitude,and the pure carbon strip easily creates arc discharge,which has a higher arc power consumption.The friction coefficient of two friction couples is decreased with the increasing of vibration amplitude,and metalimpregnated carbon has good wear resistance than pure carbon.SEM observation of the worn surfaces of the strips shows that arc erosions of pure carbon and metalimpregnated carbon are aggravated with increasing vibration amplitude within a certain range.Erosion pits and thermal stress crackings are two main arc erosion mechanisms of the pure carbon strip.A large number of furrows,pittings and spalling layers can be observed on the worn surface of the metalimpregnated carbon strip.