Preparation And Study On Tribological,Anti-corrosion Protective And Hydrophobic Properties Of MoS₂/Co Composite Coatings

Metal materials are widely used in various fields of national economy.However,the wear and corrosion of metal will cause serious accidents and bring huge losses to the economy.Electrodeposition technology is widely used to prepare metal protective coatings because of its simple operation,stable and controllable process,economical and efficient.Cobalt(Co)based composite coatings are not only environmentally friendly,but also have excellent wear and corrosion resistance.It is of great significance to improve the performance of metal parts and prolong their service life.In this study,the dispersion ability of MoS₂(MoS₂)in the electrolyte and the uniform distribution in the composite coating were improved by using ultrasonic stirring assisted pulse electrodeposition technology combined with chemical modification and ball milling stripping method,and the MoS₂/Co composite coating with excellent wear resistance and corrosion resistance and good hydrophobic properties was constructed.The influence and mechanism of dispersion ability of commercial original,modified and ball milling modified MoS₂ in electrolyte and distribution in composite coating on microstructure,chemical composition,hardness,tribological properties and electrochemical behavior of MoS₂/Co composite coating were studied.The hydrophobicity of MoS₂/Co composite coatings prepared under different current densities and the growth mechanism,corrosion resistance and wear resistance of superhydrophobic MoS₂/Co composite coatings prepared under different deposition times were systematically studied.The results show that:1.The commercial original MoS₂(O-MoS₂)is prone to agglomeration precipitation in the electrolyte,and the dispersion is poor.Polyvinylpyrrolidone(PVP)modified MoS₂(P-MoS₂)has improved dispersibility,but agglomeration precipitation still exists.MoS₂(E-MoS₂)treated by ball milling and PVP modified has excellent dispersion.2.The agglomeration of O-MoS₂ in MoS₂/Co coating results in large surface roughness,poor friction wear and corrosion resistance.P-MoS₂ in MoS₂/Co composite coating has improved agglomeration phenomenon,compact structure,hardness,friction wear and corrosion resistance.E-MoS₂ is evenly distributed in the MoS₂/Co coating,which has smooth surface,compact structure,significantly improved hardness,excellent friction,wear and corrosion resistance.3.The average current density and deposition time significantly affect the microstructure and hydrophobic properties of MoS₂/Co composite coatings.At 20 A/dm2and 30 min,a superhydrophobic MoS₂/Co composite coating with multi-scale micro-nano structure was obtained.The contact angle of the coating is 151.7°,the sliding angle is 5.2°,and the coating has good self-cleaning ability and corrosion resistance.In addition,the coating still has high hydrophobicity after sliding friction of 1200 mm on 800#Si C sandpaper,showing good mechanical stability.