Brake discs play a significant role in converting the vehicle’s kinetic energy into heat energy that is dissipated through conduction and convection. The automotive industry has been looking to develop lightweight brake discs for many years in order to reduce vehicle weight and subsequently improve fuel efficiency. In addition, the reduction of particulate matter emissions from the braking system is becoming a target, not least due to the more stringent emission regulations exemplified by the new EURO 7 regulations. In recent years, hard coatings for brake discs have been reported to be a sustainable solution for those challenges. Consequently, a great deal of development activity is currently focused on the successful use of coated brake discs. Rotor coatings and pad materials need to be adapted to each other in such a way that the required performance characteristics are reliably achieved, among other things with regard to braking performance (friction value behavior) as well as crack and thermal shock resistance. HPL Technologies has successfully developed various EURO7 homologation-capable tribosystems together with the Chair for Digital Additive Production (DAP) at Aachen University as well as with brake pad and vehicle manufacturers. Following this technical proof of concept, the focus is now increasingly on sustainable and thus environmentally friendly series production as the next step. Based on defined tribo partners, the proposed publication deals with precisely these sustainability aspects. First, the question is discussed as to which coating material and which coating height are precisely required for fine dust reduction and technical functionality (robustness), also in order to reliably achieve the service life of - as things stand today - 200,000 km or 10 years required by EURO7. The second step involves the resource-efficient production of these optimized coating systems. In particular, the reduction of powder material consumption as the number one cost driver, as well as energy consumption as biggest CO2 emission factor in the production chain, are the focus of activities with a view to environmentally friendly production optimization. The publication presents different parameter variations and sensitivity analyses for sustainability-optimized production concepts, taking into account aspects such as a stable material supply chain (multi-regional sourcing), optimized coating technology (powder efficiency, surface finish), and inline tolerance chain tuning (grinding allowance, active dimensional control). The aim of the investigations is to make the specialist audience aware of the sustainability aspects, which are usually associated with production costs in the same time.

Dr.-Ing. Phillip Utsch, Managing Director & Co-Founder, HPL Technologies GmbH; Dr.-Ing. Phillip Utsch, Managing Director, HPL Technologies GmbH; Prof. Dr.-Ing. Johannes Henrich Schleifenbaum, Chairholder, Chair of Digital Additive Production, RWTH Aachen University