Hydrophobization of tungsten carbide coatings

This study investigates the formation of superhydrophobic surfaces based on tungsten carbide coatings deposited by chemical vapor deposition and modified by laser texturing followed by treatment with hydrophobizing agents.The influence of laser treatment on the surface morphology, roughness, and wettability was analyzed in detail.The optimal superhydrophobic state with a water contact angle of 160 was achieved at 30 watts of laser power in combination with treatment using octadecylphosphonic acid.The morphology and phase composition of the coatings before and after laser processing were characterized using scanning electron microscopy and X-ray diffraction.Laser texturing was found to induce phase transformations of the initial tungsten monocarbide into a multiphase structure containing elemental tungsten and lower tungsten carbides, along with the formation of multimodal surface roughness favorable for the development of hydrophobic properties.Electrochemical polarization measurements demonstrated that the corrosion current density of superhydrophobic coatings was three times lower compared to untreated coatings, indicating significantly improved corrosion resistance.Accelerated corrosion tests in a salt fog chamber further confirmed the stability of the hydrophobic state for up to six days, although the superhydrophobicity was lost after two days.The results highlight the effectiveness of combining laser-induced surface structuring with hydrophobizing agent treatment for enhancing both hydrophobicity and corrosion protection of tungsten carbide coatings in aggressive atmospheric environments.