Brazing of C/C composite and Ni-based high temperature alloy GH3128

C/C composite and GH3128 have been vacuum brazed with BNi2 at 1 170 ℃ for 60min. The microstructure of the joint and the fracture surface were analyzed by scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). The results show that Cr atom aggregated and reacted with C forming Cr₃C₂ at the side of C/C composite, which improved the wettability of BNi2 on C/C composite. Thus the metallurgical bonding of C/C and GH3128 were achieved at the bonding zone. Cr₃C₂, MC, M3Ni2Si, Cr₇C₃ and MB formed in the brazed joint. The joint failed at the brazing zone near C/C composite, and the shear strength of the joint was 24 MPa.