Carbon Nanotube Reinforced Nickel Matrix Composites Prepared By Electrodeposition And Their Properties

Carbon nanotubes have excellent mechanical and physical properties.And they are one of the desirable reinforcement phases for Metal Matrix composite.In this research,carbon nanotubes reinforced nickel matrix composites were prepared by two-way pulse electrodeposition,and the experimental parameters were optimized.Based on the optimized process parameters,the composite materials with different carbon nanotubes content and different current density were prepared by using the surface treated CNTs.Discussed the effect of current density and other factors on wear resistance and corrosion resistance of the coating.The impurities in carbon nanotubes can be removed by purification with mixed acid,the hydrophilic groups are added on the surface of carbon nanotubes,and the carbon nanotubes are uniformly and stably suspended in the plating solution,the dispersibility of the coating in the bath is obviously improved.Uniform and dense CNTs/Ni composites were prepared by electrodeposition under the optimized conditions.The microstructure and formation mechanism of CNTs/Ni composites was analyzed by means of Scanning electron microscope(SEM),transmission electron microscope(TEM),metalloscope(OM),X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),Raman Spectrum(Raman)and microhardness.The wear resistance of composites were studied by using scratch apparatus and friction and wear apparatus.The results show that the wear resistance of the composite is better than that of pure nickel.And the friction coefficient increases first and then decreases with the increase of the amount of carbon nanotubes added in the bath,the wear resistance of 2 g CNTs/Ni was the best,and the average friction coefficient was0.343.The uniform distribution of CNTs in the composite strengthens the coating and improves the hardness of the coating.At the same time,the self-lubricating properties of carbon nanotubes play a good role in the friction and wear process.The corrosion resistance of the composite was studied by using an electrochemical workstation.The corrosion resistance of the composite was improved by adding low concentration carbon nanotubes.The reason was that the structure of the composite was denser and the corrosion medium was isolated,stopped the etch pit from spreading.