Improvements of the Si3N4 brazed joints with intermetallics

The bonding of Si3N4 ceramics with Ag–Cu–Ti, Ni and Ti was performed. The influencing factors on joint strength were investigated. Cu–Ni–Ti intermetallic particles formed in situ were observed in the joints. Scanning electron microscopy photographs show that the interfacial reaction layer is constituted of two layers. The intermetallic particles are homogeneously distributed in the matrix so that they could contribute to the decrease in the residual stresses and the improvement of the joint strength. When bonded with proper parameters, the joint shear strength can reach more than 200 MPa, with a peak experimental value of 215.33 MPa.