Research On Wear Behavior With Current Of Resin Carbon Brush Modified By Graphene

The wear behavior of Resin carbon brush is a tribological problem under the coupling function of multiple factors, existing studies to improve performance of the resin carbon brush are mainly rely on the improvements of conventional materials and technology, the development and application of new materials are obviously lags behind, and few of studies have in-depth study of the mechanism and role mode of new materials on carbon brush, as intensively investigated carbon materials, Graphene has wide application prospect in the field of electrical contact friction material. In view of the existing resin carbon brush formula is hard to combine wear-resisting and performance of friction pair matching, and difficult to achieve rational regulating of wear surface. In this paper, the influence of traditional materials such as ZnCl2, MoS2 and PTFE on wear behaviors and wear mode of resin carbon brush are studied, and have the in-depth study on the wear performance of resin carbon brush of different graphene modified ways, through characterization of the microstructure and composition of wear surface, preliminary discussion on the wear performance and wear mode of resin carbon brush modified by graphene. The main conclusions are as follows:(1) The influence of ZnCl2, MoS2 and PTFE on the wear performance and wear mechanisms of the resin carbon brush were studied, study showed that the best content of ZnCl2, MoS2 and PTFE are 2wt%, 1wt% and 1wt%, respectively. The wear surface of resin carbon brush add ZnCl2 is out of flatness and failed to form a stability lubricating film, leading to serious abrasive wear. The arc suppression gas composed of Zn, Cl2 and the oxide in the friction pair clearance are the main arc extinction mechanism. The resin carbon brush added MoS2 benefited from the synergy lubrication function, and the lubrication system can fill the wear strip pit effectively, but the worst interface compatibility of MoS2 and graphite can cause large chip off. PTFE is effective to form lubricous, steady wear surface of carbon brush and greatly reduce the wear rate.(2) The effects of directly modification method, liquid modification method and impregnation graphene dispersion three different graphene modified technologies on current-carrying wear properties of carbon brushes were researched. Results showed that the wear rate of carbon brush directly modified by graphene was decreased with increasing content of graphene, which could reduce about 28% when the quantity of graphene is 2wt%. The wear rate of carbon brush liquid modified by graphene was reduced about 38% when the graphene content of lwt%. When the dispersion solvent of graphene was choose as alcohol resin solution, the wear rate of carbon brush vacuum impregnated with graphene was reduced about 30%, and the wear rate was essentially unchanged while the dispersion solvent of graphene was only alcohol.(3) The wear mechanism of the three different modification ways of graphene were investigated in this paper, results showed that the main mechanism of carbon brush directly modified by graphene is improved the strength and lubricating property, which can reduce the risk of wear debris, and the lubrication action promoted form lubricating film on wear surface, improving the matching between the friction pair and reduce wear rate. When the resin carbon brush is liquid modified by graphene, the main effect of graphene is to increase the toughness of the resin carbon brush, as a result, enhanced the ability of wear surface resistance to mechanical wear, almost avoid the generation of wear debris and reduce the spark caused by wear debris, and reduce the wear rate. When the dispersion solvent was choosed as alcohol resin solution, graphene was fixed on the wear surface effectively, and the action mechanism of graphene is similar to resin carbon brush liquid modified by graphene, the graphene is work as toughness anti-friction material and difficult to fall off from the wear surface, directly involved in the wear progress, greatly improved the degree of friction pair matching, reduce the wear debris generated, and reducing wear and tear.