Magnesium-Aluminium (Mg-Al) alloys containing zinc or manganese are preferred choice in automobile and aerospace sectors. Aluminium, the major strengthening element in Mg-alloys is always added below its solid solubility limit of 12.5 wt.%. In the current study, Mg-Al binary systems with Al-content just below and above the solubility limit (Al = 10, 15 and 20 wt.%,) were developed and examined for their microstructural and mechanical behaviour. Microstructural studies showed the importance of Al-content in determining: (i) grain size reduction and (ii) distribution and amount of inter metallic phase. Mechanical property evaluation showed that the hardness increase was linearly dependent on Al-content, with Mg-20Al showing > 250% increase in hardness than commercial AZ91alloy. Mg-10Al showed 215% and 130% increase in yield and ultimate strengths respectively, and exhibited the best properties in terms of work of fracture, which is representative of the alloy’s toughness.

中文翻译：

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高铝含量（Al = 10、15、20 wt。％）的镁铝（Mg-Al）合金的组织和力学性能

含锌或锰的镁铝（Mg-Al）合金是汽车和航空航天领域的首选。铝始终是镁合金中的主要增强元素，其固溶度极限值始终低于12.5 wt。％。在当前的研究中，开发了Al含量刚好低于和高于溶解度极限（Al = 10、15和20 wt。％）的Mg-Al二元体系，并检查了它们的微观结构和机械性能。显微组织研究表明，铝含量在确定以下方面的重要性：（i）减小晶粒尺寸；（ii）金属间相的分布和数量。力学性能评估表明，硬度的增加与Al含量呈线性关系，Mg-20Al的硬度比市售AZ91合金的硬度增加> 250％。