| Development of marine economy will bring great economic benefits, however devices, ships and platforms which serving in the ocean not only facing harsh corrosion challenge but also suffering destruction of friction and wear during sliding process. So far, fabrication of organic coatings on the substrate surface is the most economical and efficient way to resist or alleviate the corrosion. Epoxy resin (EP) is one of the most widely used resins due to its excellent thermal, mechanical, adhesive, anti-corrosion and dielectric properties. Tribological behaviors and anti-corrosion performances of the protective coatings are crucial when they are used in the marine environment. Therefore, it is an important task to enhance the tribological and corrosion behaviors of organic coatings.In this work, the effect of molecular structure, surface morphology and internal structure on the tribological and anti-corrosion properties of epoxy composite coating on cast iron matrix were systematically studied, and thoroughly explored the mechanisms of tribological behaviors and anti-corrosion properties at micro-scale.EP coatings were cured by three kinds of curing agents with different molecular structures including chain-shaped of diethylenetriamine (DETA), ring with side-chain shaped of isophorone diamine (IPDA) and benzene-shaped of m-phenylenediamine (m-PDA). The results showed that the coefficient of friction (COF) of m-PDA cured EP coating was the highest, while the DETA cured one was the lowest due to the linear and flexible chain. The electrochemical results indicated that the anti-corrosion performance of IPDA cured EP coating was the best, while m-PDA cured was the poorest, which might be attribute to molecular structure and molecular weight which could adjust the internal crosslink network and interface structure.Based on the porous structure existed on the surface of DETA cured EP coating, the effect of surface morphology on the tribological and anti-corrosion properties of EP coating cured with diethylenetriamine (DETA) at room temperature,80℃,100℃ and 120℃ was evaluated. The results indicated that the EP coating cured at 120℃ exhibited the best tribological performance, which was attributed to the shallow surface morphologies and high hardness of EP coatings. The EP coating cured at 80℃ exhibited the best anti-corrosion performance even after 24h of immersion in 3.5wt% NaCl solution, that is due to its surface morphology and hydrophobic property.Finally, this study aslo investigated the effects of the shapes and the contents of carbon nanomaterials, served by functionalization fullerene C60 (FC60) and functionalization graphene (FG), on the tribological and anti-corrosion performances of as-prepared composite coatings. The structural characterization was examined via using FTIR, XRD, Raman and XPS, and the morphological characterization and both good dispersion and compatibility in the EP matrix were examined using TEM, SPM and TEM. UMT-3 multi-functional tribology test equipment and electrochemistry workstation were used to evaluate the tribological and anti-corrosion properties of as-prepared coatings. It was found that composite coatings showed a lower COF, wear traces area and higher anti-corrosion behavior in comparison with neat epoxy, and the optimal additive concentration of FC60 and FG both were 0.5wt%, owing to the balance of reinforcement, lubrication and barrier effects of carbon nanomaterials and cracks generated by them. Moreover, FC60/EP coatings exhibited better tribological performance but worse corrosion resistance property compared with FG/EP coatings, which was caused by the different shapes of carbon nanomaterials.
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