Preparation Of Carbon Nanotubes, Purification And Composite Coatings Research

Carbon nanotubes have aroused many scientists' interests because of its remarkable mechanic and electronic properties. So far, the investigation of the carbon nanotubes has been the hotspot of the materials, physics and chemistry.In this paper, the preparation and the purification of the carbon nanotubes was investigated. Using the Co catalysts produced by chemical co-deposition, the carbon nanotubes were synthesized by the catalytic chemical vapor decomposition method. The parameters which affect the yield of the carbon nanotubes were also studied and the optimize parameter was determined. Then the carbon nanotubes were purified by calcined in a suitable temperature after the acid-treatment. Before the calcined process, TGA was used to determine the calcined temperature. By this way, the crude was completely purified without destruction and losing.Meanwhile, the preparation of the carbon nanotubes composite coating was studied in this paper. The pure carbon nanotubes were deposited in the nickel coating by the chemical composite deposition method, and the influence of some factors in the process of the preparation was analyzed.In addition, the experimental research of the properties of carbon nanotubes composite coating such as the wearing resistance and the corrosion resistance were investigated in this paper. The wearing mechanism and corrosion mechanism were discussed. The result of the wearing experiment show that CNT composite coating have excellent wear resistance. At the same load, the dry friction coefficient of the CNT composite coating lower than that of the nickel coating and SiC composite coating. From the results of the weight-loss method and electrochemical corrosion experiment, it was founded that the potential of the CNT composite coating is more positive than that of the pure nickel coating, and the corrosion resistance of the CNT composite coating is better than that of the nickel coating, indicating the corrosion resistance of the CNT composite coating was improved due to the addition of the carbon nanotubes.