Effects of an overlapping multi-pass friction stir process and rapid cooling on the mechanical properties and microstructure of AZ31 magnesium alloy
Effects of an overlapping multi-pass friction stir process and rapid cooling on the mechanical properties and microstructure of AZ31 magnesium alloy
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DOI：
10.1016/j.matdes.2014.01.069
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发表时间：
2014-06-01
影响因子：
8.4
通讯作者：
Nourbakhsh, S. H.
中科院分区：
文献类型：
--
作者：
Nia, A. Alavi;Omidvar, H.;Nourbakhsh, S. H.
镁作为最轻的结构金属的应用正在增加；然而，它在室温下的低延展性可以被认为是一个限制。搅拌摩擦工艺 (FSP) 是一种固态工艺，可以通过生产细晶材料和均匀的质地来克服这一限制。本研究使用重叠道次 FSP 在 AZ31 镁合金表面创建细晶区域。在此过程中采用快速冷却来消除连续道次的热效应。创建了两种不同的重叠模式。在第一种模式中，样品表面在一个方向上进行 FSP 重叠。在第二种模式中，样品的第一重叠表面在垂直于初次加工的方向上再次重叠。结果表明，两种模式在加工方向上的机械强度均有所增加。第一种模式的伸长率大于原材料的伸长率，而第二种模式的伸长率小于原材料的伸长率。在垂直于工艺的方向上，材料的机械强度和延展性均小于原材料。第二模式中的颗粒分布比第一模式中的颗粒分布更均匀。 (C) 2014 Elsevier Ltd. 保留所有权利。
Applications for magnesium as the lightest structural metal are increasing; however, its low ductility at room temperature could be considered a limitation. The friction stir process (FSP) is a solid state process that can overcome this limitation by producing a fine-grained material and uniform texture. This study used overlapping passes FSP to create a fine-grained area on the surface of AZ31 magnesium alloy. Rapid cooling was employed during the process to eliminate the thermal effects of successive passes. Two different modes of overlap were created. In the first mode, the surface of the sample was FSPed overlapping in one direction. In the second mode, the first overlapped surface of the sample was overlapped again in a direction perpendicular to the primary process. The results showed that mechanical strength in the process direction increased for both modes. Elongation was greater for the first mode than that of the raw material and, for the second mode, was less than for the raw material. In the direction perpendicular to the process, both the mechanical strength and ductility of the material were less than those of the raw material. The particle distribution in the second mode was more uniform than that for the first mode. (C) 2014 Elsevier Ltd. All rights reserved.