Ceramic-matrix composites (CMC) made of carbon and silicon carbide dual matrix reinforced with carbon fibres (C/C-SiC) have exceptional heat, thermal shock, creep, and wear resistance, while also having little density and high strength. In comparison to monolithic ceramics, CMC possess ductility and damage tolerance, which opens this material for severe applications. Starting in space applications, this material is today well established in friction applications, where lightweight high-performance brakes securely decelerate e.g. luxury cars or elevators. The high production costs still limit the broad application like as brake discs in standard passenger cars, although less weight, better performance and longer life-time. The industrial used production process is the liquid silicon infiltration (LSI) with it three steps: preform shaping, pyrolysis and silicon infiltration. In this work, the shaping process of the carbon fibre reinforced plastic CFRP preform, is done by thermoset injection moulding. The application of plastic production processes like compounding and injection moulding in the liquid silicon infiltration process route, enables large-scale manufacturing. However, the screws and high shear forces inside the plastic processing machines significantly shorten the fibres.
To overcome the disadvantage of fibre length reduction, chopped carbon fibres are into the injection moulding process. This roving-based reinforcement is intended to ensure ductile material behaviour with tolerant failure. For this purpose, the chopped fibres with different length and mass shares are embedded into the CFRP preform during injection moulding, then pyrolysed and infiltrated with silicon. The chopped fibre bundles withstand the shear forces during the injection step and increase the mechanical properties of the plastic and ceramic parts. The test specimens are examined microstructurally and mechanically. Additionally, the influence of the flow direction on the orientation of the fibre bundles and their influence on microstructure and mechanical properties is shown.