PARTIAL TRANSIENT LIQUID-PHASE BONDING OF Si3N4 WITH Ti/Cu/Ni MULTI-INTERLAYERS

Partial transient liquid-phase (PTLP) bonding has been explored for joining ceramic-ceramic or ceramic-metal couples in recent years. It can produce heat resistant joints at substantially lower temperatures than those required for conventional joining approaches. Recent research has shown that Si3N4 can be successfully bonded to metal Ni by using Ti foil, where a partial transient liquid phase is formed at the Ti/Ni interface at first. The liquid phase disappears through the interdiffusion of Ti and Ni atoms. Although sufficient bonding strength was obtained, the compressive stress (20 MPa) applied reached the pressure for solid-state diffusion bonding, and the brittle compound Ni3Ti, which could reduce the joint strength, formed in the joint because of the intensive interaction between Ti and Ni atoms. In this study, a Cu foil was inserted between the Ti foil and Ni sheet. 9 refs.