The Ni plating has good corrosion resistance and wear resistance. However, the pure Ni plating is prone to undergo the defect of porosity and coarse grains, the performance of which can be apparently improved by adding a small amount of rare earth elements during nickel plating. Hence, a series of NiCoCe alloy layers was formed on the Q235 substrate by electroplating and changing the composition of the plating solution and the current density, and the changes in corrosion resistance before and after the surface treatment were evaluated by immersion tests and electrochemical experiments. Result showed that the addition of 0～0.4 g/L Ce element could effectively enhance the corrosion resistance of the coating by refining the grains. When the current density was less than 0.04 A/cm2, the increase in current density could refine the grains in coatings and improve compactness and corrosion resistance. When the added amount of Ce element was 0.4 g/L, the current density was 0.03 A/cm2 and the plating temperature was 50 ℃, the as-prepared coating obtained the optimal experimental results.
