High-Performance Protection for Chassis

At the IAA 2017 Dörken Coatings presented its zinc flake systems on safety-relevant components in the area of the chassis. / The brake discs, leaf springs and triangular control arms fitted to the test bench delivered a convincing performance - including after stone impact testing - in various cyclical stress and corrosion tests.

In the field of automobile construction, bolts, spring band clips and springs have been securely protected against corrosion with zinc flake systems for many years now. The fact that the highly-capable micro layers are also suitable for large components with difficult geometry was demonstrated by Dörken Coatings, Herdecke, with an impressive presentation at the IAA 2017 in Frankfurt. The focus of the fair presentation was a fully-assembled chassis, featuring components with original coatings as well as components coated with Dörken Coatings. The surfaces of both component groups had been previously tested for corrosion resistance in climate chambers. The Dörken Coatings system employed displayed the highest levels of corrosion resistance - including after mechanical stressing.

Chassis components are exposed to extreme static and dynamic stress, as well as constant mechanical onslaught in the form of stone impacts. To ensure the required, very high level of rust protection and long lifetime of the vehicle, especially resistant coating systems are called for. Special requirements such as the secure coating of the interior of pipe constructions can also only be satisfied via individual corrosion protection solutions. In addition, factors such as material thickness reduction for weight savings also play a role in the choice of coating system. One sensible solution for components in the area of the chassis is therefore zinc flake coating systems. These can be applied in very thin layers and are consequently particularly well-suited for components with complicated or intricate geometry. A further advantage: No hydrogen is generated in the coating process and there is therefore no risk of hydrogen-induced stress corrosion cracking. This means the zinc flake coatings are also suitable for hightensile steel. The low annealing temperature also avoids damaging the steel through excessive heat. In combination with a matching top coat, a high degree of cathodic corrosion protection is provided - including after stone impact. In addition, zinc flake systems also meet the specifications of the manufacturers’ own driving tests, thus meeting the increasingly high quality requirements of the OEMs.

At the Dörken stand at the IAA trade visitors were able to verify the performance capabilities of the Dörken Coating systems first hand. For example, a triangular control arm with a zinc flake coating that fulfilled all set requirements in salt spray testing, even after stone impact. Prestressed leaf
springs impressed after diverse cyclical stress and corrosion tests. The brake discs on display also achieved the required 500 hours in salt spray testing (SST) as per DIN EN ISO 9227 without red rust, as well as enduring an hour at a temperature of 400 degrees Celsius with no problems or alteration in the product. The coating system tested here has already been in use on hydraulic vehicle brakes for years and offers these safety relevant components the required high-performance corrosion protection in combination with a high-quality appearance.