UV-cured micro- and nanostructured smart coatings

Fraunhofer Institute for Manufacturing Technology and Advanced Materials (IFAM) has developed a drag reducing surface coating. During application, the device is moved over the surface to be coated. The paint film moves under the soft roller and is pressed the surface and structured. Due to the flexibility of the embossing foil, which forms a belt in the application device and the softness of the rollers, it is possible to coat curved or spherical components having a radius of curvature down to 30cm. The microstructure of these surfaces is derived from the microstructure of the skin of fast-swimming sharks and leads to a reduction of the surface drag by up to 8%. The key factor for significant drag reduction is the sharpness of the riblet tips. The major challenge is to avoid wear and degradation. As the idea of reducing drag came from studying the skin of sharks, it will also work and give a reduction of drag in water.