For improving the comprehensive performance of pure silver coating for power grid isolating switch, pure silver and silver - graphene composite coatings were prepared by cyanide - free environmental protection electroplating method, respectively. The microstructure and basic properties of pure silver and silver - graphite composite coatings prepared by cyanide - free electroplating method were studied. Results showed that graphene was evenly distributed in the silver coating, and with increasing the content of graphene, the aggregations of graphene were observed in some regions. Furthermore, with the addition of graphene, the coatings could still maintain good conductivity and the thermal conductivity of the coating was improved. Meanwhile, the hardness, wear resistance and corrosion resistance of the material were significantly improved. Compared with pure silver coatings, the wear resistance of composite coatings increased by more than 1 time, and the corrosion resistance increased by more than 40%. In general, the silver - graphene composite coating possessed excellent comprehensive performances, which was conducive to improve the service life of the switch contact.
