Mechanical properties of ultra-fine grained AZ91 magnesium alloy processed by friction stir processing
Mechanical properties of ultra-fine grained AZ91 magnesium alloy processed by friction stir processing
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DOI：
10.1016/j.msea.2015.01.030
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发表时间：
2015-03-25
期刊：
影响因子：
6.4
通讯作者：
Ruano, O. A.
中科院分区：
文献类型：
--
作者：
del Valle, J. A.;Rey, P.;Ruano, O. A.
分析了搅拌摩擦成形(FSP)AZ91镁合金的显微组织与力学性能的关系，并与大量的文献研究进行了比较。由于FSP过程中的发热量和沉降量对最终的显微组织有很大的影响，因此使用了几种支持装置来控制搅拌区的温度，使晶粒细化到接近0.5微米。这种组织通常决定了在室温下优异的力学性能和在高温下的超塑性行为。室温下的屈服应力表明，随着基面滑移的有利取向，霍尔取出斜率急剧下降。延性的显著变化可以用晶粒度和织构对加工硬化行为的影响来解释，这两个贡献都结合在一起。最后，通过对高温拉伸试验的分析，结合其他作者报道的数据，对AZ91镁合金的晶界滑移(GBS)机制进行了统一的描述。(C)2015爱思唯尔B.V.保留所有权利。
The relationship of microstructure and mechanical properties in a friction stir processed (FSP) AZ91 magnesium alloy has been analyzed and compared with numerous investigations in the literature. Since the heat generation and sink during FSP drastically influences the final microstructure, several backing devices were used for controlling the stir zone temperature, producing a grain size refinement down to values close to 0.5 mu m. This microstructure often determines excellent mechanical properties at room temperature and superplastic behavior at high temperatures. The yield stress at room temperature shows a sharp decrease in the Hall-Fetch slope related to a favorable orientation for slip of the basal planes. Noticeable changes in ductility are explained in terms of grain size and texture effects on work hardening behavior which joins both contributions. Finally, the analysis of the tensile tests performed at high temperature, together with the data reported by other authors, have been used to obtain an unitary description of the Grain Boundary Sliding (GBS) mechanism in the AZ91 magnesium alloys. (C) 2015 Elsevier B.V. All rights reserved.