Microstructure evolution and mechanical properties of vacuum-brazed C/C composite with AgCuTi foil

The microstructure and bonding strength of vacuum-brazed C/C composite and C/C composite with AgCuTi foil are studied. The interface structure of the brazed joint is C/C composite-TiC-eutectic structure of AgCu-TiC-C/C composite. The maximum shear strength of the joint is about 20 MPa and TiC formed at the edge of C/C composite plays a key role in the brazing process. It improves the wettability of the C/C composite and inhibits diffusion of the Ag and Cu atoms in the filler metal and C atoms in the C/C composite. The fracture mode of the brazing joint is brittle. The interface evolution in the brazing process and associated mechanism are discussed.