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

摘要

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 Al_3Mg_2 and Mg_(17)Al_(12), and one two-phase layer Mg_(17)Al_(12) and a-Mg. The tensile strength across the bonding interface is as high as 24 MPa, and the Al_3Mg_2 layer is the weak link of the bonding where fracture occurs.