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The carbon fibers as a traditional enhanced and functional filler , having excellent properties, such as high strength, high modulus, good electrical and thermal conductivity , density , and small thermal expansion coefficient . But the carbon fiber surface smoothness , absence of polar functional groups , resulting in its binding force as a filler and matrix composite small ; differential and its electromagnetic properties than metal . In order to improve the surface properties of carbon fiber and broaden its application space , can be modified on the surface of the carbon fiber processing . The electroless nickel plating of the surface of the carbon fiber can significantly improve the surface properties of the carbon fiber , given its metal conductivity, thermal conductivity , and electromagnetic properties , while maintaining the advantages of its high strength lightweight . Firstly, prepared by electroless plating method different plating coating uniformity of the thickness of the nickel-plated carbon fibers . First using orthogonal design of the carbon fiber plating nickel plating bath formulations and process conditions . According to the of orthogonal optimization results on the impact of a series of chemical plating process factors , experimental analysis . Finally the best bath formulations and process conditions , i.e. 35g / L nickel sulfate , 30 g / L sodium hypophosphite , 10g / L sodium citrate , 2 mg / L of thiourea , pH = 9-10 , plating temperature T = 60 ° C . The resultant nickel-plated carbon fibers of resistivity was 0.5 × 10-5Ω.cm. By XRD, optical microscopy (OM) and scanning electron microscopy (SEM) examined in detail the content of the reducing agent , complexing agent content , plating time , plating temperature , pH value of the bath , decentralized way to glue on NiCF coating the quality and crystallinity . And then the using self NiCF filler , polyvinyl alcohol (PVA) polymer matrix , using the sol / gel method was prepared with different concentrations of NiCF / PVA material , conducted NiCF give NiCF / PVA oriented composite material to the processing and in the magnetic field under the . Further, by a large number of experiments made ??clear the PVA gel viscosity of the solution , the relationship of time and temperature , thereby determining the optimal experimental conditions of the magnetic field orientation . Characterization by SEM, XRD, OM and resistivity tests right composites NiCF / PVA NiCF characteristics were characterized and the results confirmed that the composite material of the NiCF / PVA in a magnetic field , to achieve a NiCF the orientation distribution , the material having a conductive anisotropy.
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