Interfacial microstructure, bonding strength and fracture of magnesium–aluminum laminated composite plates fabricated by direct hot pressing

A direct hot pressing method is developed to fabricate duplex metal plates of magnesium alloy base plate and aluminum cover plate. A metallurgical bonding between the base plate and the cover plate is achieved with formation of three distinct bonding subzones, two single-phase layers Al3Mg2 and Mg17Al12, and one two-phase layer Mg17Al12 and α-Mg. The tensile strength across the bonding interface is as high as 24 MPa, and the Al3Mg2 layer is the weak link of the bonding where fracture occurs.

► A technique, called direct hot pressing, is developed for economical and convenient fabrication of magnesium-aluminum laminated composite plate.
► A metallurgical bonding between the base plate and the cover layer is achieved and the tensile strength across the bonding interface of as high as 24 MPa is obtained.
► The Al3Mg2 layer is the weak link of the bonding where fracture is prone to occur.