According to the Federal Environment Agency, the largest proportion of fine dust in traffic (approx. 60%) comes from abrasion of brakes, tires and the road. Technical solutions to reduce environmental pollution are still being tested or are not available. Expensive ceramic techniques are used for more wear-resistant tires and brake pads due to the lack of cheap alternatives. But the situation with the brake discs looks much more problematic, because there is no alternative to its manufacturing. There is no economical and above all environmentally friendly replacement. In particular due to the high loads in operation, they are one of the most stressed components on the car. Cast iron with embedded graphite is predominantly used here, but the price-performance ratio has so far justified the use of this material - despite the undisputed disadvantages.

However, this inexpensive material leads to high fine dust emissions during operation and therefore represents an immense environmental burden. The widespread coating processes such as electroplating or thermal spraying proved unsuitable as they cannot effectively protect the brake discs.

• No metallurgical bonding on cast iron
• Brittle phases, pores and cracks in the coating or connection zone
• A considerable amount of material (approx. 50% powder efficiency) and costs involved