A new laser process can incorporate biologically-inspired nano- and microstructures into the surface of materials in an instant.

The technique, which could transfer properties from the natural world to the surfaces of implants or aeroplane wings, was developed by researchers at the Fraunhofer Institute for Material and Beam Technology (IWS) and the Dresden University of Technology in Germany.

Now being marketed by spin-off Fusion Bionic, the process is designed to enhance surfaces with properties such as the lotus effect, which uses a microstructure to ensure surface dirt easily washes away in rain. Replicating the fine ripples of shark skin, on the other hand, can improve aerodynamic and hydrodynamic properties on aeroplanes and ships to save fuel.

With nature as their inspiration, many such effects have been developed by coating or applying films to surfaces. These can wear away, however, causing the desired effect to diminish over time.

The researchers developed an alternative method of permanently applying nano- and microstructures to surfaces – direct laser interference patterning (DLIP). The technique incorporates the nano- or microstructure directly into the surface using a laser, processing up to 1m2 of surface per minute.

“For a long time, lasers were much too slow to be used for finishing surfaces with large areas, compared to coating or applying films,” said Dr Tim Kunze, managing director of Fusion Bionic. “But with the DLIP process we’ve made the leap to processing large surface areas quickly.”

Using the laser as a single beam would be extremely time-consuming, the researchers said, so instead they split it into multiple clusters of beams. To apply a biomimetic pattern to the surface, the multiple laser beams are superimposed in a controlled way, creating an interference pattern. This pattern can be distributed over a wider area, allowing surfaces with large areas to be processed rapidly.

“This allows us to create virtually any structure imaginable,” said Dr Kunze. “Lotus effects, shark skin, moth eyes and many more.”

During the work at Fraunhofer IWS, the team worked closely with Dresden Professor Andrés Lasagni and Airbus to develop a microstructure that prevents ice building up on plane wings during flight. Traditionally, this is achieved by piping hot exhaust air from the engines to the wings, but this wastes energy. The researchers found that the energy required by an ice protection system decreased by 80% when the wings also incorporated a DLIP microstructure. This could be particularly useful on future electric aircraft, which will need to maximise energy efficiency.

Other projects have processed implants such as prosthetic hip joints and dental implants, to make their surfaces biocompatible or antibacterial.

Fusion Bionic is working with investor Avantgarde Labs Ventures to accelerate the development of innovative surfaces, by using artificial intelligence to develop advanced functionalities. A ‘test bench’ will also use AI to quickly predict and create the optimum surface structure for any problem.

Want the best engineering stories delivered straight to your inbox? The Professional Engineering newsletter gives you vital updates on the most cutting-edge engineering and exciting new job opportunities. To sign up, click here.

Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.

Please enable JavaScript to view the comments powered by Disqus.

Download our Professional Engineering app

A weekly round-up of the most popular and topical stories featured on our website, so you won't miss anything

Subscribe to Professional Engineering newsletter

Opt into your industry sector newsletter

Please enable Javascript on your browser to view our news.

Services for home and work

Financial help and personal support

Improving the world through engineering

Flexible spaces at our head office in Westminster, London

Helping NDT professionals obtain, renew or upgrade their qualifications

Internationally recognised manufacturer of flawed specimens in the NDT and NDE industries

© 2022 Institution of Mechanical Engineers. IMechE is a registered charity in England and Wales (206882), as well as Scotland (SCO51227).