Joining of 3D C/SiC composites to niobium alloy

Three-dimensional C/SiC was successfully joined to niobium alloy with a Ti–Cu bi-foil interlayer by a two-stage joining process: at 800 °C for 30 min under 6 MPa and at 1020 °C for 8–120 min under 0.01–0.05 MPa. The results showed that the residual Cu layer at the joining interface relaxed the thermal stress of the joint effectively, and the Ti–Cu eutectic liquid, formed by the contact melting of Ti–Cu, not only infiltrated into C/SiC, but also reacted with the SiC coating of C/SiC. These characteristics were beneficial to the joint, of which the shear strength was as high as 34.1 MPa.