Diffusion bonding of laser-surface-modified gamma titanium aluminide alloy to nickel-base casting alloy

γ-TiAl alloy was bonded to Ni-base casting alloy using a laser surface modification technique, and the effects of Ni-Cr-Ti-Al clad coatings on TiAl alloy/Ni-base alloy bonds were investigated. Interfacial defects in joints were restricted by Ni-Cr-Ti-Al clad coatings. The compositions and microstructures of Ni-Cr-Ti-Al clad coatings have significant effects on the thickness and shape of interfacial reaction layers, and sound joints with the high shear strength are achieved between laser-surface-remelted TiAl alloy and Ni-base alloy laser clad with a Ni56Cr7Ti15Al22 coating.