Hierarchical magnesium nano-composites for enhanced mechanical response
Hierarchical magnesium nano-composites for enhanced mechanical response
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DOI：
10.1016/j.actamat.2010.07.028
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发表时间：
2010-10-01
期刊：
影响因子：
9.4
通讯作者：
Gupta, Manoj
中科院分区：
文献类型：
--
作者：
Habibi, Meisam K.;Joshi, Shailendra P.;Gupta, Manoj
在这项工作中，我们已经合成和研究的机械性能的分层镁（Mg）纳米复合材料与一种新的微结构，包括增强成分，这是一个复合材料本身。具体来说，我们开发了一种纳米复合材料（或者称为II级复合物），其中整体Mg作为基质，通过另一种I级复合材料增强，所述I级复合材料包括其中嵌入纳米氧化铝（n-Al 2 O3）颗粒的亚微米纯铝（Al）基体。使用粉末冶金途径将I级复合材料研磨成Mg，然后进行微波辅助快速烧结和热挤压。与单块纯Mg相比，分级复合材料表现出显著的同时增强的强化、硬化和失效应变，以及作为水平I vf的函数的非单调机械性能。在合成的不同分级配方中，具有0.972体积% Al和0.66体积% Al 2 O3的分级水平I组合物（Mg/0.972Al-0.66Al2O3）复合材料的综合力学性能较单块Mg复合材料提高了96%，0.2%屈服强度提高了80%;破坏应变为42%，断裂功为147%。我们确定并量化了一些强化机制，这些机制可能是这种分层纳米复合材料令人印象深刻的性能的原因。(C)2010 Acta Materialia Inc.出版社：Elsevier Ltd版权所有
In this work we have synthesized and investigated the mechanical performance of a hierarchical magnesium (Mg) nano-composite with a novel micro-architecture including a reinforcing constituent that is a composite in itself. Specifically, we developed a nano-composite (alternatively referred to as a level II composite) with monolithic Mg as the matrix, reinforced by another level I composite comprising a sub-micron pure aluminum (Al) matrix in which are embedded nano-alumina (n-Al2O3) particles The level II composite was obtained by adding a small volume fraction (vf) of the ball-milled level I composite to Mg using the powder metallurgy route followed by microwave-assisted rapid sintering and hot extrusion Compared with the monolithic pure Mg, the hierarchical composites exhibited significant simultaneous enhancement of strengthening, hardening and failure strain, and also non-monotonic mechanical performance as a function of level I vf. Among the different hierarchical formulations synthesized, the hierarchical level I composition with 0.972% Al and 0.66% Al2O3 by volume (Mg/0.972 Al-0.66 Al2O3) exhibited the best overall mechanical properties compared with monolithic Mg, with an improvement of 96% in the 0 2% yield strength, 80% in the ultimate tensile strength, 42% in failure strain and 147% in the work of fracture. We identified and quantified some of the strengthening mechanisms that may be responsible for the impressive performance of this hierarchical nano-composite. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd All rights reserved