Diffusion bonding in superplastic magnesium alloys

The superplastic characteristic and diffusion bonding behavior were investigated in a commercial AZ31 magnesium alloy sheet having equiaxed grain size with an average size of 16.8 μm. The alloy behaved in a superplastic manner from 623 to 723 K, and, the present material was successfully diffusion bonded at the superplastic temperature by selecting appropriate pressure and time. The maximum of lap shear strength was 0.85 at a bonding pressure of 3 MPa and a bonding temperature of 673 K, with a bonding time of 3 h. In the specimen with high ratio of lap shear strength, the bond line was not identified by optical microscopy.