SCALABLE LIGHTWEIGHT CONCEPT FOR COMPOSITE BRAKE DISCS WITH STEEL HUB MADE OF STAMPED SHEET METAL

摘要

There are numerous solutions for a lightweight brake disc design already existing on the automotive market. Most of them consist in the separation into a cast iron friction ring and a hub, usually made of steel or aluminum. The advantage of aluminum is low mass density, use of steel sheet metal allow lower thicknesses in the hub, desirable but unachievable in a full cast iron approach. However, composite brake discs cause some new challenges, such as a simple and robust connection between the friction ring and the hub. Another important task is to avoid corrosion at the joining area caused by the environmental conditions. Apart from that, most of the concepts are viable only for a specific range of vehicle types and sizes due to costs and geometrical restrictions. A unique combination of experiences in the casting and sheet metal forming industry has led to a scalable, modular concept design, which can be adapted to any size of a vehicle: from a small city car up to a heavy duty commercial vehicle. The basic connection form is cost-effective and can be successfully applied for mid-class passenger cars. It can be technologically extended in order to meet the requirements of the higher classes or mechanically strengthened to be applicable for commercial vehicles of any type. The concept has been tested virtually by means of the finite element simulation and then trialed in the test rig conditions corresponding to given vehicle segments and manufacturers. According to the results, sufficient resistance against thermal and mechanical loading is given. The used connection secures the parts against twisting into each other as well as the thermal overextension, which could lead to the separation of both components. The next planned steps are to optimise the existing concept with the purpose to make the road test and compare with already existing solutions regarding the mass and performance.