阳极氧化法制备铝基超疏水涂层及其稳定性和耐蚀性的研究

Fabrication of Aluminum-based Superhydrophobic Coating by Anodization and Research on Stability and Corrosion Resistance

铝由于在潮湿的环境中很容易受到污染和损坏,从而严重影响了其美观性和用途。为了改善铝基材料的耐腐蚀性能,采用电化学阳极氧化法与十四酸修饰相结合的方式在铝基底上制备了超疏水涂层。通过场发射扫描电镜(FESEM)和X射线能量色散光谱(EDS)对涂层表面形貌和化学组成进行了表征。同时利用接触角测量仪、喷砂实验和电化学测试分别对涂层表面的润湿性、机械稳定性以及耐腐蚀性能进行了研究。结果表明:当阳极氧化电压为20V时,所制备的涂层为最佳铝基超疏水涂层,此时涂层的接触角为(155.2±0.5)°,滚动角为(3.5±1.3)°。其对应的腐蚀电流密度较铝基底降低了2个数量级,腐蚀电位从-0.629V正移到-0.570V,呈现出优异的耐腐蚀性能。此外,该涂层还具有良好的机械稳定性。

Aluminum（Al）can be easily contaminated or damaged after exposure in damp environments,which can adversely affect its aesthetic appearance and desired functionalities.To improve its corrosion resistance,a superhydrophobic coating was fabricated on Al by electrochemical anodization followed by modification with myristic acid.The surface morphology and chemical composition were characterized by using a field emission scanning electron microscope（FESEM）with attached energy dispersive X-ray spectrum（EDS）.The surface wettability,mechanical stability as well as corrosion resistance were also investigated by contact angle measuring system,sandblasting test and electrochemical measurements.The results show that the optimal Al-based superhydrophobic coating with a static water contact angle of（155.2±0.5）°and a sliding angle of（3.5±1.3）°is obtained at the anodization voltage of 20 V.The corresponding corrosion current density（Icorr）is reduced by 2 orders of magnitude and the corrosion potential（Ecorr）shifts from-0.629 Vto-0.570 Vcompared to the bare Al substrate,indicating excellent corrosion resistance.Besides,the as-prepared optimal Al-based superhydrophobic coating also suggests good mechanical stability.