Preparation Of Electrodeposited Ni-Co-Graphene Composite Film And Research On Micro/Nano Mechanical Properties

In this study,a high-quality nanocrystalline nickel-cobalt-graphene composite coating was prepared on the surface of copper substrate by electrodeposition technology.The content of corresponding elements in the prepared composite coating can be indirectly controlled by changing the content of graphene added in the liquid and the content of cobalt salt in the liquid.In order to explore the influence of different content of graphene on the properties of the composite coating.Using scanning electron microscope(SEM)and energy spectrometer(EDS),X-ray diffraction(XRD),transmission electron microscope(TEM),microhardness meter(FM700),micro/nano mechanics comprehensive test system,the electrochemical workstation(Versa STAT3)for the preparation of nanocrystalline nickel-cobalt-graphene composite coating the microcosmic surface,phase composition,microstructure,element content,microhardness,antifriction property,nano-mechanical properties and corrosion resistance had been used to characterize.The research results of formula 1 with high cobalt content show that: when the graphene content is 0.03g/L,the coating has the best antifriction property and the maximum microhardness of 596HV;phase analysis shows that the change in carbon content is positive for(111)The crystal plane has a great influence;the mechanical properties of the entire composite coating are uniform and good at the nanometer level.When the content of graphene in the plating solution is 0.05g/L,the graphene entering the coating is the most,and the carbon content in the coating is up to 2.57%.At this time,the composite coating has the best corrosion resistance,and its corrosion potential is-0.707 V.The results of formula 2with low cobalt content show that the maximum microhardness of the composite coating is648 HV when the content of graphene is 0.05g/L.When the graphene content is 0.1g/L,the coating has a light abrasion mark and a small fluctuation of friction coefficient curve,with the minimum average friction coefficient of 0.7538.At the nanometer level,the overall mechanical properties of the composite coating are stable and uniform.When the graphene content is 0.25g/L,the coating has the best corrosion resistance,and its corrosion potential is-0.804 V.In general,under this formula,we should reasonably add graphene according to the performance of the composite coating we need,so as to achieve the desired effect.The purity of graphene was examined by transmission electron microscopy.Two kinds of nanocrystalline nickel-cobalt-graphene composite coatings with graphene content were selected to verify whether graphene entered the coating smoothly.The microstructure of two kinds of composite coatings was observed and analyzed.Comprehensive comparison and analysis of the nano-mechanical properties,antifriction property and corrosion resistance of the nanocrystalline nickel-cobalt-graphene composite coatings.