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 structures 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(circle)C for 60 min, which produced the joint with the maximum 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.