Ceramic matrix composite (CMC) materials based on 2D-carbon fibrepreforms show high heat-absorption capacities and good tribologicalas well as thermocechanical properties. 'To take advantage of thefull lightweight potential of these new materials in hith performanceautomotive brake discs, the thermal conductivity transverse to thefriction surface has to be high~ in order to reduce the surfacetemperature. Expermental tests showed that lower surface temperaturesprevent over- heating of the brake's periphery and stabilizes tbcfriction behaviour. In this study different design approaches withimproved transverse heat conductivity have been investigated byfinite elenment analysis. C/C-SiC bolts as well as SiC coatings andcombinations of them have been inivestigated and compared with anorthotropic brake disc. showing a reduction of temperature ot up to50 . Original sized brake discs `with C/C-SiC have been manufacturedand tested under real conditions which verified the calculations.Using only low-cost CMC materials and avoiding any additionalprocessing steps. the potential of C/C-SiC brake discs are veryattractive under tribologtical as well as under economical aspects.
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