Brazing of C/C Composites using a developed Au-Ni-W Filler

Brazing is a suitable method for assembling C/C composite material parts. However, active metal brazing filler damaged the C/C composite parts owing to reaction with carbon fibers and the difference of thermal expansion between the filler and the carbon matrix.The development of active metal brazing filler that can wet on C/C composite surface while protecting carbon fibers is necessary. We attempted a brazing using an Au-Ni alloy brazing filler containing of tungsten. The produced brazing filler was placed on the emerged carbon fiber surface of the C/C composite by grinding the carbon matrix. The brazing filler could wet the C/C composite. There was no excessive infiltration into the C/C composite and interfacial delamination by thermal stress. Elemental analysis of the bonding interface revealed the presence of AuNi rather than WC. It was demonstrated that the Au-Ni-W brazing alloy can wet while protecting carbon fibers.