Carbon fiber/silicon carbide (C/SiC) composites have the potential to overcome the shortcomings of the currently used carbon and metallic friction materials in aircraft brakes. In the present work, chemical vapor infiltration (CVI), melt infiltration (MI) and polymer impregnation and pyrolysis (PIP) were used to fabricate materials for mechanical, thermal and frictional tests. PIP materials exhibited the best mechanical properties, followed by MI and CVI materials. In the case of thermal testing, MI materials were superior to the other materials. C/SiC friction coefficients were higher than the values obtained for a typical carbon composite. Wear rates of the ceramic materials were comparable to the values obtained for C/C.

A single‐filament microcomposite consisting of 143‐μm‐diameter CVD SiC, a thin “interfacial” coating, and a thick (130–160 μm) CVD SiC matrix sheath was tested in tension to determine the interfacial shear properties of carbon and BN interfacial coatings. Load/displacement and acoustic emission were used to determine the mechanical behavior of the microcomposites and matrix cracking. Optical and electron microscopy were performed to confirm the extent and nature of matrix cracking and to analyze the micro‐composite microstructure. The interfacial properties were determined from matrix cracking and load/displacement hysteresis techniques. Direct measurement of the interfacial sliding stress from push‐out and pull‐out experiments were in good agreement with two of the three microcomposite systems studied.

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