Microstructure and properties of magnesium AZ31B–aluminum 7075 explosively welded composite plate

A composite plate of Mg alloy (AZ31B) and an Al alloy (7075) was fabricated by explosive welding. The microstructure and properties of the bonding interface after explosive cladding were investigated. The results show that the bonding interface had a wavy appearance with solidified melts in a regularly spaced pattern of discrete regions. Adiabatic shear bands and twin structure were found on the AZ31B Mg alloy side. “Metallurgical bonding” of the explosive welding interface was achieved by local diffusion with an approximate 3.5 μm thick diffusion layer. No intermetallics were formed. Shear strength across the bonding interface of AZ31B/7075 composite was ca. 70 MPa. The maximum bending stress reached 670 MPa.