Microstructure and creep properties of Al/Mg/Al composite clad plates

Abstract

Due to their poor plasticity and corrosion resistance, as well as their flammability in the air, magnesium alloys are limited in large-scale application. To address the above issues, magnesium alloys can be combined with aluminum alloys with superior plasticity and flame retardancy, resulting in high strength and good plasticity of composite laminates at room temperature, and lighter weight. Therefore, this article selects 5052 aluminum alloy as the outer layer of the laminated plate and AZ31 magnesium alloy as the inner layer material to study the effect of the precipitation of intermediate compounds at the interface of this laminated material under high-temperature creep conditions on the creep properties of the material. The results showed that the layer thickness of Al/Mg/Al laminate composite was about 50 mm. The main orientations of 5052Al alloy were (001) and (101) directions, while the main orientations of AZ31Mg alloy were (011̄0) and (1̄21̄0) planes and the slip and twinning behaviors at the interface of the plane occur simultaneously. The interface between the laminated plate and the two-phase matrix is a coherent interface, which confirms the principle that the lowest energy is the main reason of the high creep performance of the composite plate.

摘要 : 镁合金的塑性和耐腐蚀性差以及在空气中易燃等性能限制了其大规模应用. 为解决上述问题, 将镁合金与塑性和阻燃性能优越的铝合金结合, 可使复合层合板材料得到室温高强度和良好塑性, 并有更轻的质量. 为此, 本文选用 5052 铝合金作为层合板外层, AZ31 镁合金作为内层材料, 研究该层合板材料在高温蠕变条件下的界面处中间化合物的析出相对材料蠕变性能的影响. 结果表明, Al/Mg/Al 层合板的复合层厚度大约为 50 μm, 5052 铝合金的主要取向为(001)和(101)方向, 而 AZ31 镁合金的主要取向为( 011̄0) 和 (1̄21̄0) 面, 界面处滑移和孪晶行为会同时发生; 层合板界面处与两相基体都为共格界面, 符合能量最低原理, 是复合板高蠕变性能的主要原因.