Surface conditioning of carbon-fiber ceramic rotors against organic pads

Carbon - fibre reinforced ceramic composites are seeing wider use with performance and prestige road vehicles as brake rotors. They offer numerous advantages over grey cast iron (GCI) equivalents, primarily in their reduced density and improved maximum servicing temperature. Their extremely low wear rates imply that they have the potential to outlast their GCI counterparts several times over. Conditioning the surface of the rotor prior to friction testing can aid the engineers to improve and tailor the subsequent performance to the design requirements. In this paper, we are presenting the development of such surface conditioning procedures through a screening study on a laboratory scale bench top dynamometer, followed by validation on an industry scale dynamometer under an industry standard AK Master testing regime. The study demonstrates that surface conditioning can produce a significant impact on the friction performance of non-metallic rotors when they are coupled with organic pads. The friction surfaces are characterised by using analytical techniques, including surface profiling, hardness and indentation testing, optical and electron microscopy. It is noted that conditioning can lead to a more sustainable friction surface through enhancing both mechanical and chemical bindings on the friction surface of the rotors . We will discuss the possible factors that could fundamentally govern the friction performance of the friction couple under certain testing conditions.