The effect of deposition potential on the structure and performance of the Ni-Co multilayer nanocrystalline coating

The effect of different deposition potential for electrochemical additive manufacturing prepared the nano-multilayer Ni-Co alloy coating was investigated. The Ni-Co alloy coatings are FCC structures according to XRD analysis . As the potential becomes negative, the weight ratio of Ni in the plating layer increases, and the thickness of the plating layer also increases. Meanwhile, the more negative potential reduces the crystallite size (between 15 nm and 44 nm) and increases the hardness of the Ni-Co coating. The corrosion tested for 3.5 wt% NaCl showed that the thinner multilayer structure will suffer significant penetration corrosion, and the thicker multilayer structure can slow down the penetration corrosion.