Research On Friction And Wear Characteristics Based On Sliding Electrical Contact Testing Instrument

Electric locomotive get power and energy by sliding contact between pantograph andcatenary wire. Catenary wire and pantograph constitute a pair of friction，electric locomotive canoperate reliably or not，the key is whether get stability current from the catenary or not. The mainfactors of pantograph system friction and wear are：the contact pressure，contact temperature，contact current，the operating speed of electric locomotive and so on. The change of them willmake different variation of friction coefficient，wear rate and contact resistance.With the research background of electric railway in this paper, the wear mechanism ofsliding electrical contact is deeply studied by considering the pantograph slide as the main objectof study. The Cu impregnation carbon strip rub against the Cu-tin wire to research thefriction-wear characteristics of the Cu impregnation carbon strip under sliding electrical contactconditions and a lot of experiments were carried out with a self-developed sliding electricalcontact testing instrument. The following obtained conclusions：The friction coefficient increaseswith the increase of contact pressure. The curve of wear rate of strip and contact pressure isshown that the wear rate firstly decreases and then increases. There is a threshold of contactcorresponds to minimum wear rate to keep lower wear rate. The contact resistance decreaseswith the increase of contact pressure and the contact resistance change rate decreases with theincrease of contact pressure. At different contact currents，the friction coefficient，the wear rateand the contact resistance of strip have different changes degree with the increase of contactpressure. Under dry friction，the friction coefficient firstly increases and then decreases withincreasing temperature. At current，the friction coefficient decreases with increasing temperature.Under dry friction and current conditions，the wear behaviour both increase with increasingtemperature. The friction coefficient decreases with the increase of sliding speed，the wear rateincreases with the increase of sliding speed. The friction coefficient decreases with the increaseof contact current，the wear rate and contact resistance both increase with the increase of contactcurrent.By studying on the friction and wear of pantograph system friction，summed up underdifferent contact conditions(contact pressure，contact temperature，sliding speed，contact currentand so on)，the different variation of friction coefficient，wear rate and contact resistance. It ishelp to clearly understand the problem which pantograph system need to be resolved，and seek solutions to the problems，so as to lay the foundation for future research，and then solve practicalengineering problems.