Preparation of Ni–B composite coating doped with hydrothermally modified synthetic WC@MoS2 powders via ultrasonic-assisted jet electrodeposition for corrosion protection

Abstract

This work aims to improve nanoparticle agglomeration, which hinders the application of nanoparticles in enhancing coating properties. Superhydrophobic and corrosion-resistant Ni–B– MoS2@WC composite coatings were prepared with the help of a simple and inexpensive combination of hydrothermal and electrodeposition techniques. Hydrothermal treatment at 180°C for 24h greatly reduced the specific surface area and improved the hydrophobicity of WC@MoS2 powder. The WC@MoS2 powder showed good dispersion stability in the electrolyte solution. Ni–B/WC@MoS2 composite coatings were prepared through codeposition with metallic Ni2+ under the action of ultrasonic waves. WC@MoS2 powder doping induced the coatings to exhibit a selective orientation of the (111) crystal plane. Ultrasound-induced cavitation increased the participation of nanopowders in the adsorption codeposition of Ni ions. After WC@MoS2 powder doping, the surface roughness of the prepared composite coatings furthered significantly, facilitating the wettability transition. This work investigated the relationship between the surface wettability of the coatings prepared via jet electrodeposition and WC@MoS2 powder doping under auxiliary ultrasonic power. In addition, the effect of surface hydrophobicity on corrosion resistance was examined through electrochemical corrosion tests. The enhanced corrosion resistance of the composite coatings benefits from their enhanced surface roughness and superhydrophobicity. This research offers a proven strategy for improving nanopowders' wettability and composite coatings' corrosion resistance.