PARTIALLY TRANSIENT LIQUID PHASE-DIFFUSION BONDING ON Ti(C, N)-Al2O3 CERAMIC MATRIX COMPOSITES USING Zr/Cu/Zr AS INTERLAYER

The partially transient liquid phase-diffusion bonding(PTLP-DB) on Ti(C, N)-Al2O3ceramic matrix composites(CMC) was studied using the Zr foil/Cu foil/Zr foil sanwich as an interlayer. Effect of holding time during PTLP-DB on the element diffusion and reacted products at the interface was analyzed and the affected factors on the joint strength during PTLP-DB were explored. The effect of auxiliary pulse current during PTLP-DB between CMC on element diffusion at the interface and joint strength and its mechanism were also studied. The results showed that the optimum holding times were 15~30 min during PTLP-DB on CMC at 950 ℃. With a shorter holding time, the joint strength decreased due to the existance of unreacted Zr elements at the interface, while with a longer holding time, the joint strength decreased due to the overgrowth of CuZr intermetallics at the interface. With the auxiliary pulse current during PTLP-DB, the residual stress at the interface was greatly decreased, which inhibited the propagation of crack into the base materials. While, the auxiliary pulse current can promote the reaction between Cu and Zr and the formation of Zr-Cu intermetallics at the interface, which produced a weaked interface in the joints.