Study On Preparation Of Anodized Aluminum-based Biomimetic Surfaces And Their Anticorrosion And Antifouling Properties

Mold fouling during vulcanization is a widespread issue faced by tire industry that urgently needed to be addressed as it can degrade comprehensive performance of molded products and increase production time for cleaning mold,resulting in tremendous economic loss and resource consumption.Here,inspired by the antifouling and self-cleaning function of plants such as lotus leaf and Nepenthes in nature,a novel and promising fouling mitigation strategy is presented.Imitating the multi-scale structure and low surface energy characteristics of lotus leaf and Nepenthes,two kinds of biomimetic surfaces(micro nano multi-scale surface and slippery liquid-infused porous surfaces)are prepared on 7050 aluminum alloy by anodic oxidation technology,and their hydrophobicity,electrochemical corrosion resistance,self-cleaning performance and antifouling behavior under sulfurization condition are studied.The main research contents of this paper are as follows:1.Study on preparation of micro nano multi-scale surface and their anticorrosion and antifouling properties.By adjusting the anodizing parameters and modifying with low surface energy materials,micro nano multi-scale structures is prepared on the surface of aluminum alloy.Scanning electron microscopy(SEM),Contact angle tester,Energy dispersive X-ray spectroscopy(EDS)and Fourier transform infrared spectroscopy(FTIR)are used to characterize the microstructure,hydrophobicity and surface composition of Biomimetic surfaces.At the same time,electrochemical corrosion test,self-cleaning test and vulcanization test are carried out on the modified micro nano multi-scale surface.Results show the following.The synergistic effect of micro nano multi-scale structure and low surface materials endows the aluminum alloy with superhydrophobic properties,and the optimum hydrophobic angle is 152°.The modified micro nano multi-scale structure has excellent charge shielding effect,significantly improved corrosion resistance,low adhesion and excellent self-cleaning performance.However,the micro nano multi-scale structure is not suitable for antifouling under sulfurization conditions.2.Study on preparation of micro nano structured SLIPS and their anticorrosion and antifouling properties.Inspired by the structure of Nepenthes,a low surface tension lubricant is loaded on the superhydrophobic surface to prepare micro nano structure SLIPS.The stability,corrosion resistance,self-cleaning and rubber adhesion resistance of the coating are studied by high temperature stability test,full immersion test,antifouling test,electrochemical corrosion test and ZSimp Win circuit fitting.Results show the following.Compared with superhydrophobic surface,SLIPS is more stable at high temperature and full immersion.SLIPS has the best corrosion resistance,higher self corrosion potential and lower corrosion current density.In addition,the self cleaning mechanism of SLIPS is different from that of superhydrophobic surface,but it still performs well.Under the condition of vulcanization,SLIPS can play an antifouling function,and has more durable rubber adhesion resistance.3.Study on preparation of nanostructured SLIPS and stability properties.Nanostructures are fabricated on the surface of aluminum alloy by two-step anodization process,and nanostructured SLIPS are prepared by low surface energy modification and vacuum negative pressure oil loading technology.The effects of hierarchical structure on the static contact angle,slip angle hysteresis and the stability of lubricant stock are studied by shear test.Results show the following.The surface layer structure can affect the stability of the SLIPS to the lubricant,and its ability to preserve the lubricant is not equal to the ability to maintain the characteristics of the SLIPS.Among them,micro nano structure can store lubricant most effectively,and its oil retention capacity is 4.4 times of that of smooth surface.But nano structure can form a more stable lubricating film with a very low slip angle hysteresis(< 2°).In addition,15 vulcanization tests show that the surface of nanostructured SLIPS has better rubber adhesion durability.