Investigation on nickel/alumina-nanoparticles co-deposition

Ni/Al₂O₃-nanoparticles composite microcomponents with thickness of 300 μ are fabricated for micromechanical workpieces by using a combination of UV-lithography and micro electroforming. An effective and low cost process for electroplating the composite microcomponents using a spraying assistance is developed in this paper to disperse the alumina nanoparticles uniformly. The dispersing state is simulated presumably by using hydrokinetics finite element analysis. The simulated results show that the mass of tiny laminar flows and whirlpools caused by spraying riptides would be helpful to prevent the nanoparticles from reuniting and maintain the suspended state of nanoparticles around the cathode surface. The experimental results show that the alumina nanoparticles are uniformly dispersed in the microcomponents during the co-depositing process with the spraying assistance. The spraying-deposition process not only improves the dispersing condition of alumina nanoparticles but also promotes them to be adsorbed and deposited uniformly onto the cathode surface. The micromechanical properties of the composite components are also tested. The data shows that the mechanical properties of the components are significantly improved compared with the pure nickel components.