Interfacial Microstructure of AZ91 Bonded by Transient Liquid-Phase Diffusion with Amorphous Interlayer

Transient liquid phase(TLP) bonding processes had been performed to join two AZ91 base magnesium alloy using Mg65Cu25Gd10 amorphous ribbons as interlayer. Welding experiments were performed at the temperature 480 degrees C 500 degrees Cand 520 degrees C for different times (3 hours to 5 hours) under pressure of 1 Mpa. The microstructures of TLP bonding joint zones were analyzed employing optical microscopy, X-radial Diffractometer(XRD) and electron probe analyzer(EPMA). The dissolution width increased when the bonding temperature and holding time increased. The diffusion of the elements during the process was studied interlayer alloy and base metal alloy elements diffused into each other, the sophisticated chemical reactions among the Mg65Cu25Gd10 amorphous interlayer and AZ91 base metal created a large number of intermetallics.