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Starting in the late '90s, a new and innovative brake disk technology entered the high performance passenger car market. Approx. 2 years later, small volume production of carbon-ceramic brake disks started. In the past ten years the number of cars equipped with the new generation of ceramic matrix composite (CMC) brake disks has continuously increased, with main usage in low volume, high horse power applications. The goal of this paper is to give an overview of the system specific boundary conditions as well as today's and tomorrow's targets and aspects of friction material development used in CMC-disk based brake systems. Starting with a description of the system component properties, a comparison of typical CMC vs. standard gray cast iron disk (GCI) applications will be made. The impact of the component properties, especially the disk as friction counterpart to the pad, will be shown by comparing industry standard test scenarios.

Over the last two decades, intensive research in the field of innovative brake rotor materials for high performance vehicles has been done. Due to the market demand for lightweight components with high strength even at elevated temperatures, most new concepts are based on fiber-reinforced materials [1]. The most prominent concept is a silicon carbide matrix material with embedded carbon fibers (C/C-SiC), which penetrated into the market for brake rotors in 2000 [2,3]. Such carbon ceramic brake rotor systems (CKB) have already been made available for a wide range of premium sedans, SUVs and sports cars. In terms of tribology, these rotors pose new challenges for an understanding of the relevant friction phenomena in the boundary layer, as well as for suitable formulations of brake pad materials. The brake system's macroscopic tribological performance with such pads is determined by a closed-loop interaction between heat, wear and sliding resistance on the micro scale.