In this study Al2O3–Cu core-shell nano structural composites, are fabricated through two step electroless coating process of pretreatment and Electroless deposition. This kind of nanocomposites can be used as the catalysts, electromagnetic wave absorbing materials, contactors, switches and etc, because of their excellent properties such as good electrical and thermal conductivities and excellent corrosion and wear resistance. The influence of various electroless parameters on the thickness and uniformity of coated layer are investigated and because of numerous experiments needed an experiment design based on Taguchi robust design method is applied. The parameters are: Pretreatment type (1step, 2step and 3step), HCHO/CuSO4.5H2O ratio (10/10, 10/15, and 10/20ml/g), C4H4O6KNa.4H2O concentration (40, 50 and 60g/l), PH (11,12 and 13) and Pouring rate (3 and 5ml/min). The morphology, uniformity, and chemical composition of the Cu coated Al2O3 particles were characterized by XRD, SEM and TEM and it is concluded that the 3step pretreatment method, 10ml/l HCHO, 20g/l CuSO4.5H2O, 60g/l C4H4O6KNa.4H2O, PH=11and Pouring rate of 5ml/min are the best condition for Electroless deposition of Cu. During the electroless plating of activated Al2O3 particles, nucleation of nano-sized copper particles was started from the Pd clusters and subsequently more nucleation and growth of copper was performed onto the catalyst Cu nucleies and surface of Al2O3 particle and caused to coat the surface of Al2O3 particle and form a uniform Cu shell with thickness of 20nm around the Al2O3 core.

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