Abstract:  An investigation of transient liquid phase (TLP) diffusion bonding of a Ni₃Al-base directionally solidified superalloy, IC6 alloy, was presented. The interlayer alloy employed was Ni-Mo-Cr-B powder alloy. The results show that the microstructure of the TLP diffusion bonded joints is a combination of γ solid solution (or a γ+γ′structure) and borides. With the bonding time increasing, the quantity of the borides both in bonding seam and adjacent zones is gradually reduced, and the joint stress-rupture property is improved. The obtained stress-rupture property of the TLP bonded joints is on a level with the transverse property of IC6 base materials.

Key words:   Ni₃Al-base superalloy; TLP diffusion bonding; stressrupture property