Erosion resistant anti-ice surfaces generated by ultra short laser pulses

Wetting properties of a wide range of materials can be modified by accurate laser micromachining with ultra short laser pulses. Controlling the surface topography in a micro and sub-micrometer scale allows the generation of waterrepellent surfaces, which remain dry and prevent ice accumulation under certain conditions. The use of ultra short pulse lasers provides a method to generate a pattern on the surface of hard materials with micrometric scale features that are required for reaching the super-hydrophobic state. Water repellent structures usually have a poor structural strength and as a result their properties are quickly deteriorated when used under working conditions; hence a durable surface is highly desired. The combination of laser processing with plasma techniques provides the means to create robust Lotus-like structures. This paper investigates the anti-ice properties of plasma deposited hard coatings, e.g. diamond-like carbon, in combination with laser machined patterns. These hard coatings with reduced surface energy and adjustable surface topography improve the erosion resistance of super-hydrophobic surfaces, and make them more suitable for use under harsh environmental conditions.