Effect of inert gas-shielding on the interface and mechanical properties of Mg/Al explosive welding composite plate

Mg alloys oxidize easily in air atmosphere during explosive welding. In this study, explosive welding of Mg/Al composites was shielded using inert gas to improve composite quality. Mg-AZ31B/Al-1060 composite plates were produced under helium atmosphere and compared with identical plates produced under air atmosphere with the same parameters. Microscopic morphology, elemental distribution and the mechanical properties of the bonding interface were evaluated. The interface morphology of the composites welded under helium differs significantly from those welded under air due to the different pressure of shock waves in gaseous media, and almost no oxide formed on the interface of helium bonded composite. In addition, the gain of shear and tensile strength of the helium bonded samples were observed. Therefore, the inert gas plays an important role in improving the properties of Mg-Al composite plates. Inert gas-shielding can be applied as an effective manufacturing method in live wave metal explosive welding.