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 20V. The corresponding corrosion current density (Icorr) is reduced by 2 orders of magnitude and the corrosion potential (Ecorr) shifts from -0.629V to -0.570V compared to the bare Al substrate, indicating excellent corrosion resistance. Besides, the as-prepared optimal Al-based superhydrophobic coating also suggests good mechanical stability.
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