| The electroplating nickel process is widely used throughout the world for decorative ,engineering purpose. Traditional decorative electroplated nickel coatings are lustrous, smooth and mirror-bright. Electrodeposition is a convenient method to fabricate the composites. The effects of many experimental parameters on the electro-composites were introduced in this paper. In all of the experimental parameters ,such as pretreatment of particles, cathode current density, particle concentration, agitation, pH value and charge on the particle surface, the more important parameters are current density, particle concentration and agitation. In this dissertation, we have investigated satin nickel electroplating and incorporated with micron particles and nanometer particles in a nickel matrix. The main results are as following:1,When using WD-20 by our investigation, a good appearance of Satin Nickel coating has been obtained in the conditions of medium temperature, wide current density and agitation-free.A pearl appearance of Satin Nickel coating has been obtained by adopting a newly type of electro-plating Satin Nickel Cloud Point-free process. The effects of bath compositions and technological parameters on the coating appearance had been studied. The bath solution is more stable and the working period of bath solution is longer than other Satin Nickel plating processes. In addition, the appearances of coatings scanned by SEM shows the different appearance from other coatings, which indicated the additives used in this new process should have different function on electroplating process compared with other traditional Satin Nickel additives.2, A technique about Ni-SiCh electrocodeposition processes has been presented in the paper. The influences of bath composition and technological parameters, such as pH value, stirring speed , current density, particle concentration and additives, to the coating appearance and behavior have been studied. The results show that the crystal minimizing agent and bright agent can be used to improve the coating appearance. SEM photographs show that the coating is fine and SiO2 particles are well distributed in the coating. The amount of SiO2 is between 10-22wt% in the Ni-SiO2 coatings.3, Electrodeposited coatings incorporating nano-TiO2 in the nickel matrix have been obtained in the Watts solution. The effects of bath composition and technologicalIVparameters on the coating have been studied. The appearance and components of Ni-nano-TiO2 coatings have been characterized by the SEM method. The results show the amount of nano-TiCh in the coatings reached at 5-10 wt%, and the appearances of coatings are fine and nano-TiC? particles are well distributed in the coating.4, The cyclic Voltammetry and Electrochemistry Impedance Spectroscopy have been used to study the behavior of Ni2+ on the Au, Pt electrodes. Adding the different additives agent have caused the different results. The CV experiment results indicate that B agent could adsorb on the electrode surface to increase the,electrochemical-polarization of Ni2+ and minimize the crystal size. But it makes the oxiding peak more negatively. When added A agent in the solution, it decreased the cathode polarization of Ni2+ and made the current distribution uniformed and wide the range of current density. Agent A, B both can increase the impedance of Ni2+. EIS results show that Agent A,B can influence the behavior of nickel deposition.5,The corrosive behaviors of bright nickel in pH=3,5% NaCl solution are uniformly and linear corrosion. All of the Ni-based composites have passive phenomena. The anti-corrosive ability of Ni-nano-TiOj coating is more highly than those of the other of the composites.The corrosive weightlessness experiments of the composites in the NaCl solution show the anti-corrosion ability sequence: Ni-TiO2>Ni-micron-SiO2 >Satin Ni>Bright Ni. This result is the same as that of anodic polarization.
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