Joining of C-C composite with BNi-1a

In this study, Carbon-Carbon (C-C) composite joints were prepared using BNi-1a paste filler metal as the intermediate layer in a vacuum brazing method. The interfacial struc- tures and compositions of the joints were analyzed using scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray diffraction (XRD). The results show that element interdiffusion and chemical reactions occurred in the joining zone, and various compounds were formed, including Cr3C2, Ni31Si12, Ni(s.s), MB and MC (M = Cr, Fe, Ni). The optimum joining parameters were determined to be the brazing at the temperature of 1120°C for 60 min, which produced the joint with the maxi- mum shear strength of 24.13 MPa. The joint shear strength and fracture morphology demonstrate that bonding temperature and retention time have a significant effect on the strength of C-C composites.