In this interview Dr Georg Wagner, Managing Director of the innovative company NTC Nano Tech Coatings GmbH, based in Tholey, Saarland, explains how functional coatings on metal surfaces in the automobile industry can become even more effective through a simple paradigm shift …

Nano coating use has become more common in the automotive industry in recent years. Corrosion protection is usually the property upon which this use is based, but the same product often also has additional functional properties, the most frequent of which being the easy-to-clean function.

Dr Wagner, as a supplier to the automotive industry, is this also the basis for your business?

Dr Wagner: This type of nano coating is based on the sol-gel process, which leads to the formation of hybrid polymers during curing, thus resulting in a highly cross-linked product with interpenetrating inorganic and organic polymer structures. The coats display outstanding adhesion to the substrates and provide excellent corrosion protection while achieving low dry film thicknesses of just a few micrometres. FUSCO technology by NTC Nano Tech Coatings GmbH, however, represents a further development of sol-gel technology. It is based on the same fundamental principles and produces very high media resistance levels. This means, among other things, that it can be used on anodised surfaces, such as the exterior add-on components that are used in the automotive sector by international vehicle manufacturers.

Where else is FUSCO technology used?

Dr Wagner: These coatings have also been used for many years in heat exchangers in order to drastically minimise surface contamination. Here, the FUSCO effect results in easy-to-clean properties that are not based on the lotus effect. The surface that this produces is not structured, but rather creates a very smooth barrier layer with pronounced non-stick properties. This significantly improves mechanical resistance, with the effect remaining stable for years.

Hydrophilic materials, which are also used in some cases, allow moisture to adhere to the surface, whereas hydrophobic coatings do not cause any build-up or corresponding contamination. This effect achieves very good results in industrial applications on heat exchangers. The FUSCO materials work very well and effectively in this application although the prevailing theory calls for hydrophilic surfaces here. A paradigm shift in this area leads to surprising results and some industrial practitioners are showing the courage to successfully embrace a “reversed” interface, producing very good results.

Does this mean that heat exchangers coated with a FUSCO material last longer and perform better throughout their service life? 

Dr Wagner: Exactly, that’s a simplified way of expressing it. All the effects of the materials described here are achieved without the use of PFAS and are long-lasting. This industrial application began over 20 years ago, and it is also being used increasingly in the automotive industry. The use of coated heat exchangers not only protects against corrosion, but also reduces energy consumption, thanks to surfaces remaining clean.

Alongside these already established product properties, further properties are increasingly being added that are being brought to application maturity. In this way, in certain modifications, it has been possible to drastically reduce the adhesive strength of ice that has condensed on the surface and reproducible anti-ice properties are being implemented. This allows different types of built-up ice to be removed from the substrate with little effort.

Dr Wagner, Thank you for speaking with us.

 Bild: NTC