Study on Preparation of Superhydrophobic Ni-Co Coating and Corrosion Resistance by Sandblasting–Electrodeposition

To enhance the corrosion resistance of type C45E4 substrates, a superhydrophobic Ni-Co coating was prepared on a C45E4 surface by sandblasting pretreatment and electrodeposition. The surface microstructure, three-dimensional surface roughness, and crystal structure of the coating was characterized by scanning electron microscope, laser scanning confocal microscope, and X-ray diffraction. An optical surface contact angle measuring instrument and an electrochemical workstation was used to characterize the wettability and corrosion resistance of the surface. The results showed that the water contact angle reached 151.2 degrees on the Ni-Co coating surface. The surface was superhydrophobic and still had stable hydrophobicity after four months. In electrochemical corrosion experiments. Compared with polishing pretreatment, the corrosion current density of superhydrophobic Ni-Co coating prepared by sandblasting pretreatment reached Icorr = 5.05 × 10−7 A·cm−2, and the corrosion potential reached Ecorr = −0.33 V. The superhydrophobic Ni-Co coating had excellent corrosion resistance.