Fabrication of metal matrix composites via casting methods is under attention due to poor wettability of reinforcement particles within the metallic matrix. In order to improve wettability of reinforcement particles in different metallic matrix, surface of reinforcement can be modified with different metallic coating agents. Nickel and copper are favor coating agent, and can be deposited on the surface of particles by electroless deposition (ED) method. However, in electroless deposition it is difficult to obtain uniform and nano-sized metallic coating on the nanoparticles. In this study, copper coating Al2O3 micro and nano particles by ED studied. In order to reach to the maximum efficiency of electroless deposition, the effect of ED parameters, such as concentration of Al2O3 particles, bath temperature, plating time, stirring speed and Al2O3 particle size, optimized by Taguchi method. Through optimization the process, maximum plating rate and optimum properties of coated layers (uniformity, optimum composition and minimum thickness) considered as desired outcomes. The morphology, uniformity, and chemical composition of the activated and Cu coated Al2O3 particles were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The results show that, Bath temperature with 61.35% contribution; plating time with 23.7% contribution and Al2O3 concentration with 12.81% contribution have the most influences on the process plating rate, respectively.

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