Abstract: A new superplastic diffusion bonding technique combined with laser surface modification to join Ni based alloy with γ-TiAl based alloy is proposed. Microstructures of laser surface modified coating on the substrate of intended bonding alloys are studied,and diffusion bonding of Ni based alloy with γ-TiAl based alloy is discussed. The results show that the laser surface modification improves the bonding quality of joint, and sound bond is achieved at 850℃ with a pressure of 60MPa in 1hour plus post heat treatment at 900℃ in 0.5hour.

Key words: γ-TiAl based alloy, laser surface modification, diffusion bonding, coating