Research On Friction And Wear Property Of Copper Alloy Conducting Wire Under Electric Current

According to the particularity of friction and wear behaviors of electro-contact lead materials, to provide reliable experimental and theoretical basis for general adoption of market principle of new-style electro-contact lead wire materials by continuously directional solidification technology, MS-T3000 Mul-function Material surface performance tester, was modified .the modified device structure is simple and easy to operate,.moreover, the data acquired by test is proved to be exact. Single or multiple factors control on voltage, as well as current, speed, load can be continuously adjusted within certain range. Friction and wear behaviors of electro-contact materials with and without current can be measured on the tester.Unlubricated sliding experiments on monocrytal copper and Cu-0.1%WT Ag alloy with brass as frictional pair have been made under different load, speed, current. The effects of different factors on the friction and wear performance of electro-contact lead wire materials were analyzed. at the same time, we analyzed the wear behaviors and wear mechanism . In addition, taking self-lubricate material which is made of bronze and graphite as fictional pair, analysed the effect of lubricate on the friction and wear properties of monocrytal copper and Cu-0.1%WT Ag alloy. The experimental result shows:Under non-current non-lubricate sliding conditions, with the increasing of load, the friction coefficient of monocrytal copper and Cu-0.1%WT Ag alloy first decrease then increase. The relationship between mass wear rate and load displays linear increasing feature. With the same load, the mass wear rate of monocrytal copper is higher than that of Cu-0.1%WT Ag alloy. With sliding speed increase ,the friction coefficient decreases gradully. With small load, the wear rates slowly reduces along with the increase of sliding speed. With big load, along with speed increasing, mass wear rate first reduces then increases.Under non-lubricate with current conditions, when having small current, the friction coefficient and wear rate of monocrytalline copper and Cu-0.1%WT Ag alloy become small; when current exceed some critical value, the friction coefficient and wear rate of monocrytal copper and Cu-0.1%WT Ag alloy will become very big. When taking self-lubricate material as fictional pair, because of lubricate effect, the friction coefficient and mass wear rate greatly reduced. The fluctuation range of friction coefficient is very small, the current, sliding speed and load have little effect on the friction coefficient and wear rate.By analyzing the worn surface of the contact wire and collected wear debris of SEM micrographs, it indicated that without current, the main wear form is grain wear. under small load, while fatigue wear is the main wear form under high load. Under current, when having small current, the main wear forms are adhesive and oxidation wear; when having big current, oxidation and erosion wear are the main wear form.