A Feasibility Study of Superhydrophobic Coating on Al6061 for Airplane Anti-icing Applications

Abstract

Ice protection systems are essential for all airplane operational missions to ensure safe and reliable operation of air transport. Typically, size and contact area of cold droplets are the deciding factors for the type of ice spreading over the airplane surface. Preparation of superhydrophobic surfaces has received a great attention in the recent years to minimize the ice nucleation over the airplane skin. In this article, Aluminum alloy Al6061 is used to prepare a protective, textured superhydrophobic coating through chemical spray coating techniques. A cost-effective superhydrophobic coating has been developed by chemical etching and spray coating of copolymeric silicone composition that is confirmed by Infrared technique. Morphological studies by optical microscope show a micro-nano rough pattern that increases with the weight percentage content of the silicone film sprayed after drying. At an optimum 5% of silicone, contact angle reaches a maximum value of 154 ± 2°. This superhydrophobic coating offers interesting icephobic properties and the Aluminum surface is tested for its ice repelling property by spraying the supercooled liquid over the surface. The anti-icing coated substrate was further tested for wear and corrosion properties to meet the airworthiness standards. This superhydrophobic coating can be applied for various offshore applications such as wind turbines, and automobile windscreens as it reduces ice adhesion to achieve higher safety measures.