The Ni-Cr-P metal powder was prepared by vacuum melting and inert gas atomization method, and then an organic binder was added and stirred at high speed to prepare a Ni14Cr10P paste-like filler metal. The prepared pasty filler metal was used to braze the C/C composites in a vacuum furnace. Then the shear strength of the brazed joint was tested. The interface structure of the brazed joint was analyzed by OM, SEM, EDS and XRD. The results show that the shear strength of the joint obtained at the brazing temperature of 1000℃ and the holding time of 0.5 h reaches 28.6 MPa, and then the strength of the brazed joint is decreased with the increase of the brazing temperature or the holding time. It is found that the contact area between the brazing layer and the surface of the C/C composites is increased by the pasty brazing filler metal, which is favorable for blocking the pores on the surface of the C/C composites. A staggered distribution of Cr carbide phase buffer layer is formed at the interface, so that the interface exhibits a structure with an increased thermal expansion coefficient gradient, which helps to alleviate the thermal mismatch and improve the strength of the brazed joint.
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