The effect of annealing on the interface microstructure and mechanical characteristics of AZ31B/AA6061 composite plates fabricated by explosive welding

In this investigation Magnesium alloys AZ31B/Aluminium alloys 6061 composite plates were obtained successfully through the method of explosive welding. The effect of annealing on the evolution of interface microstructure and mechanical properties of the composite plates were investigated. The results demonstrated that the AZ31B/AA6061 composite plates were bonding well. On annealing at and above 250 degrees C, intermetallic compounds of Al3Mg2 and Al12Mg17 were observed to form at the bonding interface. By increasing the annealing temperature, the tensile strength of the composite plates increased firstly, then it was dramatically decreased, while the elongation increased significantly. This behaviour was considered to be due to the diffusion of Mg and Al elements as well as the formation of intermetallic compounds during annealing process. Crack propagation and interface delamination were observed of the composite plates annealed at and above 250 degrees C. Corresponding fracture mechanisms of the composite plates were also analyzed. (C) 2014 Elsevier Ltd. All rights reserved.