Influence of Fiber Fabric Density and Matrix Fillers as well as Fiber Coating on the Properties of OXIPOL Materials

Higher efficiency of jet engine and environmental friendly use are promised via an increase of the combustion temperature. Oxide ceramic matrix composites (CMC) are reliable candidates for this purpose. Within this scope, the German funded project HiPOC (High Performance Oxide Ceramics) supports the further development of OXIPOL (Oxide CMC based on Polymers) materials at the German Aerospace Center (DLR) in Stuttgart. The OXIPOL materials studied in this work are manufactured via the polymer infiltration and pyrolysis process (PIP) and reinforced with alumina fibres (Nextel 610, 3M). A variation of the fibre fabric density (i.e. filament number) and the fibre volume content is firstly investigated. Moreover, the influence of ceramic fillers on the interlaminar shear strength (ILSS) as well as the influence of different types of fibre coating (fugitive and lanthanum phosphate coating) on mechanical behaviour are discussed. This work showed that OXIPOL materials with lower filament number present a more homogeneous fibre coating in the bundle and a better matrix infiltration, leading to an improvement in mechanical properties.