Study on Electrochemical Etching Process and Performance of Superhydrophobic Surface of 6061 Aluminum Alloy

ABSTRACT The corrosion problems of 6061 aluminum alloy in the marine atmospheric environment are becoming increasingly serious. To alleviate the corrosion problems in the chloride‐ion environment, electrochemical etching technology and stearic acid chemical modification are used to prepare superhydrophobic micro‐nanostructures on its surface. Through different electrolyte configurations and orthogonal tests, the optimal process parameters are obtained using contact angle as evaluation index. The contact angle measuring instrument, scanning electron microscope, energy dispersion spectrometer, X‐ray diffractometer, Fourier transform infrared spectrometer and electrochemical workstation were used to study its hydrophobicity, surface morphology, phase composition, chemical composition and corrosion resistance. The results show that the optimal process parameters of electrochemical etching are: current density 0.6 A/cm 2 , electrolyte concentration is 0.3 mol/L sodium chloride and 10 g/L citric acid, treatment time 6 min, electrode gap 8 mm. Following parameter‐controlled etching modification, the contact angle reached 152.9°, with a 49.7% reduction in corrosion current density.