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Cf/SiC composite and Ti alloy (TC4) were successfully joined by the mixed powders of Ag, Al, Ti and short carbon fibres under vacuum condition. The Microstructure of the joints was investigated by X-ray diffraction, scanning electron microscopy and energy dispersive spectrometry. The results show that the good chemical bonding and reactive composite brazing joints are obtained by reactive composite brazing with both (Ag-6Al)+Ti and (Ag-6Al)+Ti+C filler materials. The addition of short carbon fibres contributes a lot to the shear strength by alleviating the thermal stress of the joints and to the in situ synthesised TiC which surround the uniformly distributed short carbon fibres. Ti element can improve filler metal's wettability to Cf/SiC composite and restrain the oxidation of Al element. The max shear strength obtained is 90·8 MPa and the optimal parameter is brazing at 910°C within 10 min. [ABSTRACT FROM AUTHOR]

Carbon fibre reinforced SiC (Cf/SiC) was successfully joined to Ti alloys with Cu-Ti-C mixed powder by brazing. Microstructures of the brazed joints were investigated by SEM, EDS and XRD. The mechanical properties of the brazed joints were measured by a mechanical testing machine. The results showed that the performed joints have dense bonding layers reinforced by residual graphite and in situ synthesised TiC from the reaction of C and Ti in the bonding layers. The composite brazing layers relaxed the thermal stress of the joints effectively. These characteristics were beneficial to the joints, of which the shear strength was remarkably higher than the optimal shear strengths of the joints brazed with pure Cu-Ti. [ABSTRACT FROM AUTHOR]