Superhydrophobic and anticorrosion Ni-B/WC@MoS2 composite coatings deposited via jet electrodeposition assisted with ultrasonics

Abstract

BackgroundElectrodeposited surface coatings are used as an important protective measure for metal surfaces such as bearings. Enhancing the corrosion resistance of the coating is the key to practical application. MethodsNi-B/WC@MoS2 composite coatings deposited on 45-steels were prepared by ultrasound-assisted jet electrodeposition combined with hydrothermal modification of nanoparticles. The impact of ultrasonic power on the composite coatings’ physical phase structure, micro-morphology, surface roughness, surface hydrophobicity and corrosion mechanism were evaluated. Significant FindingsUltrasound-assisted power helped to enhance the deposition of WC@MoS2 powder for the composite coatings. The coating surface prepared with the assistance of 270 W ultrasound showed a dense "cauliflower" shape with a superhydrophobic surface contact angle of 153.7° The composite coating assisted by 270 W ultrasonic power was found to have the largest corrosion potential (-218 mV) and the smallest corrosion current (6.8E-07 A/cm2) after the electrochemical corrosion test. The polarization resistance of the coating was 35,568 Ω·cm2, and the measured corrosion rate was 8.0E-3 mm/a. It was three orders of magnitude lower than that of the composite coating without ultrasonic power assistance. The Ni-B/WC@MoS2 coatings obtained with jet electrodeposition assisted by 270 W ultrasonic wave showed good corrosion resistance.