Corrosion resistance study of Zn-Ni-B4C composite superhydrophobic coatings with hierarchical rough structure

The composite electrodeposition was used to successfully prepare Zn-Ni-B4C composite superhydrophobic plating with single γ-Ni5Zn21 phase and hierarchical micro/nanostructures on Q235 steel. The addition of micron B4C particles promoted the formation of micron protrusion structures and the change of current density promoted the development of hierarchical rough structures. Electroplated plated layers were electrodeposited at a current density of 5 A·dm−2 for 30 min and modified with an ethanol stearate solution to achieve a water contact angle of 159°, exhibiting excellent superhydrophobicity. Simultaneously, the superhydrophobic plating exhibits good anti-corrosion performance, and the corrosion current density of the plating in 3.5 wt% NaCl solution decreased significantly by 1 order of magnitude compared to the zinc-nickel alloy plating. After 96 h of immersion, the anti-corrosion performance was higher than the untreated Zn–Ni alloy plating, and the plating was still superhydrophobic after modification by stearic acid ethanol solution.