Bioinspired superhydrophobic surfaces on AA 6082 with improved corrosion resistance

Despite the considerable demand for superhydrophobic surface (SHS) for different applications, it is still difficult to establish a suitable manufacturing process. In the present work, a simple strategy for SHS fabrication on AA6082 by consecutive hydrothermal treatment and silane coating was reported. The hydrothermal treatment duration showed an important influence on the morphology, wettability and corrosion resistance of the samples. The SEM showed the growth of a boehmite after the first few minutes of treatment. Increasing the time, the boehmite film became more dense and homogeneous. Thirty-minute sample showed the best wettability results (CA=180°; SA=0°) and an improvement of the corrosion resistance compared to bare aluminum (Ecorr increased from -870 to -298mV and Icorr decreased from10-2 to 10-6mA/cm2). The SHS Bode plot showed two time-constants instead of one and the |Z| increased by one order of magnitude, due to the effective protective action of the SHS coating.