Abstract
Si3N4 ceramic was joined to itself using Cu76.5Pd8.5Ti15 alloy filler at 1373 to 1573 K for 1.8 ks in a vacuum. The room-temperature bending strength of the Si3N4/Si3N4 joint reached a maximum value of 155.8 MPa when the brazing temperature and holding time were 1423 K and 1.8 ks, respectively. The joints were composed of three parts: (1) TiN reaction layer at the ceramic/filler interface; (2) bonding layer (TiN, CuTi and Pd2Si) connecting with the reaction layer; (3) Cu based solid-solution in the middle of the joint, and the reaction phases (Pd2Si, PdTiSi, Ti5Si3, TiN) existing in the Cu solid-solution. With increasing brazing temperature, thickness of the reaction layer and amount of the reaction phases increased, which improved the bending strength of the joints.
