Current-carrying Tribological Properties of Ti-Ag/TiN-Ag and Ti-Cu/TiN-Cu Coatings under Grease Lubrication

The Ti-Ag/TiN-Ag and Ti-Cu/TiN-Cu coatings are prepared by multi arc ion plating. The conductive grease(MLG) is prepared with multilayer graphene(MLG) as conductive filler and polyethylene glycol(PAG) as base oil. The friction and wear properties of the coating under the condition of current carrying lubrication are studied by hft-r4000 high-speed reciprocating current carrying friction and wear tester. The surface of the coating and wear mark are observed and analyzed by scanning electron microscope(SEM), energy dispersive X-ray spectrometer(EDS) and Raman spectrometer(Raman). The results show that the Ti-Cu/TiN-Cu coating with Cu atom content of 3% has better anti-wear, anti-friction and electro-corrosion properties under grease lubrication, while the Ti-Ag/Ti N-Ag coating with Ag atom content of 3% shows better current stability under grease lubrication, which is attributed to the composite effect between the coating and grease to improve the friction reduction, anti-wear and conductivity of the friction surface.