Graphene reinforcement of nickel-cobalt matrix nanocomposites by different type of current electrodeposition

Ni-Co alloys are notable alloys used widely in industry because they have very good wear resistance, high degree of strength and heat conductivity. It is known that third phase addition to alloys improves the properties of them. Graphene has become very popular as a reinforcement material since it has large specific surface and very good electrical, optical, mechanical etc. properties. Electrodeposition is an important coating method because the parameters of the process can be controlled easily during coating process, it doesn't require neither high temperature nor high pressure which result in cost increase and it can be applied complicated shapes. It is known that electrodeposition current type changes coating properties. In this study copper plates were coated by nickel cobalt alloy and graphene reinforced nickel cobalt metal matrix nanocomposites by electrodeposition coating method. Current types were changed in coating processes. Direct current (DC), pulse current (PC), pulse reverse current (PRC), and ramp current types were applied during electrodeposition. Phase analysis, surface morphology, mechanical and tribological properties were examined. It was observed that properties of coating are enhanced by current type and adding graphene. The best results were obtained when PRC type was used. Keywords: Ni-Co, graphene, coating, nanocomposite, electrodeposition.