Effect of the Cassie Baxter-Wenzel behaviour transitions on the corrosion performances of AA6082 superhydrophobic surfaces

Turning the wetting behaviour of a solid surface from hydrophilic to hydrophobic by making morphological and chemical modifications has attracted great attention over the past few years due to the importance of these surfaces in fundamental research and industrial applications in particular for anti-corrosion purpose. In this work, a chemical etching-based approach, which can be easily scaled to industrial level, was proposed to obtain super-hydrophobic surfaces on 6082-T6 aluminium plates. The results showed that the wetting transitions from Cassie-Baxter to Wenzel regime and vice versa can be controlled by changing the etching time. The mechanism at the basis of the wetting behaviour is based on the nanostructure roughness. In addition, the as-prepared aluminium surfaces revealed a good corrosion resistance behaviour in seawater compared with the as received one. The relationships between the corrosion performances and the Cassie Baxter-Wenzel behaviour transitions were deeply discussed.