Studies On The Nickel Plating Of Carbon Fibers With Two Scales And The Coating Properties

Carbon fiber materials in different scales have more important applications in the aerospace, automotive, new energy and other industries. Polyacrylonitrile(PAN)-based carbon fibers is a kind of filamentous fibers made with PAN precursor through a series of complex processes, which contain more than 90% carbon content. It is a widely used reinforced material with high specific strength and modulus, and low density, low expansion coefficient, wear resistance, corrosion resistance, excellent performance, low resistivity. Carbon nanofibers are carbon nanomaterial made up of curly and stackable multilayer graphite and prepared by chemical vapor deposition and gas phase pyrolysis of hydrocarbons. Its size is between the carbon nanotubes and carbon fibers. CNFs have higher specific surface area, great length-diameter ratio and dense structure.Because of the high specific surface energy of carbon fiber and carbon nanofibers, there are the problems of poor wettability and easy oxidability under high temperature service conditions when its add into matrix materials. Therefore, it’s very important for carbon fiber materials to improve their the compatibility of the base material and enhance its interface binding force with the base material through surface treatment.Surface treatment and electrochemical plating nickel of carbon fiber materials are the effective way to improve the interface compatibility and effective way to enhance the interface bonding force.In this paper, surface degumming of carbon fiber adopt the method of cleaning with acetone or burning. Before and after nickel plating, the degumming effect, micro topography, resistance and oxidation resistance of carbon fiber were analyzed. The result show that the burning treatment has better degumming effect than acetone cleaning. The burning process of degumming is optimum under burning 20 min at 400 ℃. The micro topography of carbon fiber show its surface is more smooth and the resistance of carbon fiber reduce in the optimum burning process. After nickel plating, the oxidation temperature of carbon fiber raised to 650 ℃, which increased 200 ℃ in comparison to the carbon fiber without nickel coating, and the resistance of carbon fiber decreased significantly from 29.9Ω to 1.24Ω.Carbon nanofibers is treated by mixed acid or surfactant and then prepared into paper. The micro topography and physicochemical properties of carbon nanofibers papers were measured.Compared with acid treatment, surfactant treatment method can obtain lower resistance carbon nanofibers paper without fiber breaking, but its stability of the dispersion liquid is weaker. Compared the micro topography of nickelizing, carbon nanofibers paper of nickel-plated with surfactant treatment show the better effect. Nickel-plated film is formed well on the carbon nanofibers surface. Further, carbon nanofiber sheet with nickelizing improve its oxidation resistance and magnetic property and reduced its electrical resistivity.