Interfacial microstructure and mechanical properties of brazing carbon/carbon composites to stainless steel using diamond particles reinforced Ag-Cu-Ti brazing alloy

In this manuscript, diamond particles were used as reinforcement in the Ag-26.7Cu-4.5Ti (wt.%) brazing alloy for joining carbon/carbon composites (C/C) to stainless steel (316). The effects of the volume percentage of diamond particles on the microstructures and mechanical properties of the brazed joints were investigated. Experimental results show that the diffusion-reaction layer was formed between the interlayer C/C composite due to the element interdiffusion, the diffusion layer adjacent to the C/C composites thickened gradually as diamond contents increased. Concomitantly, Cu (s.s) distributed more diffusely and uniformly to occupy the whole brazing seam. The apparent shear strength of the joints is 53 MPa using 15 vol.% diamond particles in Ag-Cu-Ti brazing alloy, which is about twice as high as that of joints without diamond particles. But excessive diamond particles added to the brazing alloy leads to cracks and pores resulting in poor strength of the brazed joint.