Microstructure Regulation and Synergistic Deformation of As-Sintered Al and Mg Alloy During Roll Bonding

In this paper, the problems of bending and edge cracking in the 2A12-Al/AZ31-Mg laminated metal composites (LMCs) prepared during roll bonding (RB) were studied systematically. The results show that the formation of bending and edge cracks is due to the difference in microstructure and mechanical properties between as-sintered 2A12 aluminum alloy (S-2A12-Al alloy) and as-sintered AZ31 magnesium alloy (S-AZ31-Mg alloy). This leads to the different plastic deformation ability of the two alloys, and they cannot achieve synergistic deformation during RB. The synergistic deformation of the two plates can be achieved by pre-rolling deformation and annealing treatment before RB. This can effectively solve the bending and edge crack problems of 2A12-Al/AZ31-Mg LMCs during RB. Therefore, the S-2A12-Al alloy was first pre-rolled with 40% reduction at 300°C and then annealed at 420°C for 60 min, while the S-AZ31-Mg alloy was pre-rolled with 60% reduction at 300°C. Finally, the pretreated S-2A12-Al alloy and S-AZ31-Mg alloy were roll-bonded at 300°C, and the 2A12-Al/AZ31-Mg LMCs, with no bending or edge cracks, were successfully prepared.