The effect of homogenization on the microstructure and mechanical properties of transient liquid phase bonding between Inconel 718 and Inconel 600

In this paper, the effect of homogenization on the microstructure and mechanical properties of transient liquid phase bonding between Inconel 718 and Inconel 600 using BNi-2 interlayer was investigated. The homogenization was performed on the bonded samples at 1050°C for 45 min which have not any eutectic compounds. The homogenization was done at 1080°C for 6 hr and 12 hr and 1180°C for 1 hr,2 hr, and 3 hr. The results indicated that at the temperature of 1080°C for 12 hr, compounds of DAZ on Inconel 718 side were almost completely vanished. On the other hand, the homogenization was completed at 1180°C for 3 hr and any boride compounds was not observed in the DAZ of Inconel 718 and Inconel 600 alloys. When homogenization was complete, the hardness value of DAZ was decreased and this value equated to the hardness value of base metals. The results of bonding shear strength showed that the joint strength was significantly increased with elimination of the diffusion effected zones.