Silicon carbide fibres with different diameters were extruded. Fibre diameters in the range of 150 to 500 μm have been realised. For the fibre manufacturing, SiC ceramic powder was mixed with different amounts of a commercially available binder system in a torque rheometer. Their viscosity and the homogeneity were characterised by capillary rheometry. For the binder burnout process, the components were characterised by thermal gravimetric analysis. Under the used binder burnout conditions about 17 wt% of the wax Licomont and 4 wt% of the polyethylene Lacqtene PEBD formed a binder residue. Tensile strength measurements on 500 μm fibres from 6 different feedstocks were performed. It has been shown, that fibres with a low amount of binder (11 wt%) had the best mechanical properties (σ_0 = 381 MPa). Variation of the ratio of wax to polyethylene had no influence on the mechanical strength. Fracture surface analyses on sintered fibres were performed by optical microscopy.
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