Abstract：By using high energy mechanical ball milling, the nickel-cobalt based nano-Al₂O₃ composite electro-brush plating solution was prepared, then the distribution state of nanoparticles in plating solution was discussed and its effect on the electrochemical properties was also analyzed. The particle-size analyzer and infrared spectrometer were used to test the size of nanoparticles and its adsorption characteristics. The electrochemical workstation was used to test the cathodic polarization curve and cyclic voltammetry response of the nano-composite electro-brush plating solution. The results show that the size of nanoparticles in plating solution is about 100 nm, some kinds of charged ion and functional group are adsorbed on the surface of nanoparticles, and the surface potential is negative, so the polarization negative shift and the response current decreases. All of the above characteristics of nanoparticles are good for the co-deposition of nanoparticles and nickel-cobalt alloy.

Keywords：nanoparticle; electro-brush plating; composite plating solution; co-deposition