Fabrication and characterization of superhydrophobic surfaces on aluminum alloy substrates

Superhydrophobic surfaces have potential anti-icing applications in industries and daily life. In the present study, we combine the methods of chemical etching and surface modification with H-1, H-1, H-2, H-2-perfluorooctyltriethoxysilane (POTS) which has very low surface energy to simplify the fabrication procedures for superhydrophobic surfaces on aluminum alloy substrates. The results show that the contact angle (CA), rolling angle (RA) and contact angle hysteresis (CAH) of superhydrophobic surfaces etched with 8.0 wt% HCl aqueous solutions are 162.5 degrees, 1.9 degrees and 1.1 degrees, respectively; the apparent surface free energies (ASFEs) of superhydrophobic surfaces increase with the decrease in surface temperature; the freezing time of water droplets on superhydrophobic surfaces is retarded by 1568s, and the temperature drops to as low as -11.9 degrees C. The results indicate that superhydrophobic surfaces exhibit excellent anti-icing properties. (C) 2014 Elsevier B.V. All rights reserved.