Aluminium alloys are widely used in various industrial sectors thanks to the combination ofproperties such as low density, high specific strength and relatively low cost. However, such alloysare usually particularly susceptible to corrosion, leading their durability in aggressive environmentsto be the limiting factor in industrial field applications.In the last years, nature inspired super-hydrophobic surfaces acquired a large interest due to theirpotential and promising use for corrosion resistance applications. The creation of superhydrophobicaluminium surfaces can be a suitable and effective solution to overcome corrosionresistance issues.In the present paper, a super-hydrophobic surface with micro and nano hierarchical roughness wasobtained on 6082-T6 aluminium substrate by three different surface pre-treatments: i) immersion inboiling water, ii) wet chemical etching in HNO_3/HCl solution (volume ratio 1:3) iii) wet chemicaletching in HCl and HF solution (73% and 5%, respectively, in distilled water water 22%).Afterwards in situ polymerisation process through octadecylsilane coupling agent was carried outon all pre-treated surfaces. Eventually, all substrates were dried for 3 h at 100 °C to complete thesilane curing.Preliminarily, the effect of aluminium surface treatment on wettability and morphology of thealuminium substrate surface was assessed. The micro and nano rough structure of aluminiumsurfaces was evaluated combining scanning electron microscope and atomic force microscopeanalysis. The super-hydrophobic behaviour was assessed by performing water contact angle(WCA) measurements by sessile drop tests. Finally the electrochemical behaviour of the surface in3,5 %wt. NaCl solution was evaluated by performing electrochemical impedance spectroscopy(EIS) measurements at increasing immersion time up to 7 days of immersion.The results showed that all surface treatments stimulated the formation of a rough and irregularmorphology with very high WCA. Best results were observed for HF etched Al 6082 surface wereWCA about 175° was achieved. The as-prepared surfaces revealed good corrosion resistancebehaviour in 3.5%wt. NaCl solution. However, for all batches, a progressive reduction in impedanceperformance at increasing immersion time has been also identified. In such a context, based onpromising results, further developments aimed to optimize the surface treatment process andensuring higher durability in an aggressive environment will be stated.
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