Abstract:This article investigates a straightforward, highly effective, and eco-friendly technique for preserving carbon steel surfaces against corrosion, by depositing Cu-Ni alloy coatings on the workpiece"s surface to impede corrosive medium. The effects of current density and Cu2+ concentration on the composition, morphology, and composition of the coating were investigated using scanning electron microscopy, X-ray energy dispersive spectroscopy, Vickers hardness tester, friction and wear tester, and electrochemical testing. A cauliflower like Ni rich protrusion structure appears on the coating surface. The lower current density and Cu2+ concentration affect the Vickers hardness and wear resistance of the coating by affecting the grain microstructure and Cu/Ni content, both leading a decrease in hardness and wear resistance. When the current density is 10 mA/cm2 and the Cu2+ concentration is 0.1 mol/L, the corrosion current density of the deposited sample reached 1.389×10?5 A·cm?2, and its surface corrosion damage was significantly less than that of the sample without coating after 24 h of salt spray test. Research on the deposition mechanism indicates that Cu2+ undergoes instantaneous nucleation under diffusion control, tending towards vertical growth and forming cauliflower-like protrusions, while Ni2+ is controlled by electrochemistry to discharge uniformly across the surface.