2020 Volume 58 Issue Supplement Pages 107s-112s
The Al/Mg clad materials were produced by vacuum roll bonding. After bonding, the clad materials were heat treated at different temperatures. The growth of intermetallic compounds on Al/Mg bond interface was investigated. The results show that the growth of intermetallic compounds was very slow at 200℃ and only Al3Mg2 layer with 2 μm thickness was observed after 3h. Al3Mg2 and Al12Mg17 intermetallic layers were formed at and above 300℃, and the growth activation energy of Al3Mg2 (86.18 kJ/mol) is smaller than that of Al12Mg17 (115.33 kJ/mol), so the growth of Al3Mg2 is faster and thicker. The thickness of intermetallic layer has a great influence on the tensile strength of Al/Mg interface. When the thickness of the intermetallic layer exceeded 20 μm, the tensile strength reduced to less than 6 Mpa. After 200℃ heat treatment, ductile fracture and brittle fracture occurred simultaneously at Al/Mg interface during tensile test. After heat treatment at and above 300℃, the fracture of Al/Mg interface occurred in the intermetallic layer and mainly in the Al3Mg2 layer, and the mode of fracture were cleavage fracture.
