The Quality and Hardness of the Al–Mg Welded Joint under Different Modes of Explosion Welding

This study investigates the effect of different explosive thicknesses (38 and 47 mm) on the interface macrostructure and Vickers micro-hardness of 5052 aluminum and AZ31 magnesium alloy explosive weld joints. The interface macrostructure, closer to the detonation point, showed a straight interface, while the middle and end sections exhibited a wavy morphology, irrespective of the explosive thickness. The interfacial waves in the middle zone had smaller amplitudes and wavelengths, which increased toward the tail section of the weld. The amplitude/wavelength ratio in the middle and tail regions ranged between 0.17 and 0.25 for both explosive thicknesses, confirming the formation of smooth waves. Vickers hardness increased with explosive thickness, with the highest hardness observed near the collision interface. The positioning of the experimental condition is the weldability window, an analytical estimation, is presented as well.