Plastic deformation behavior of Mg89Zn4Y7 extruded alloy composed of long-period stacking ordered phase
Plastic deformation behavior of Mg89Zn4Y7 extruded alloy composed of long-period stacking ordered phase
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DOI：
10.1016/j.intermet.2010.02.011
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发表时间：
2010-05-01
期刊：
影响因子：
4.4
通讯作者：
Umakoshi, Y.
中科院分区：
文献类型：
--
作者：
Hagihara, K.;Kinoshita, A.;Umakoshi, Y.
研究了Mg 89 Zn 4 Y 7（at.%）合金的形变行为。主要由长周期堆积有序（LPSO）相组成的挤压合金，在室温下进行了研究。在400 - 525 ℃的温度范围内对挤压合金进行了几次热处理，并定量研究了显微组织与力学性能之间的相关性。挤压态合金的屈服应力显示出类似于480 MPa的极高值。挤压态合金的变形伴随着变形扭折和少量非基面滑移的形成。挤压合金的显微组织是高度热稳定的，并且屈服应力在低于400 ℃的热处理下几乎没有变化。然而，通过在400 ℃以上退火，屈服应力逐渐降低。在475 ℃及以上退火的合金的屈服应力随退火温度的升高而不连续地降低。退火试样的屈服应力可以通过将板状晶粒长轴的长度视为晶粒尺寸的Hall-Petch关系来估算。这表明由随机取向晶粒组成的LPSO相合金的塑性行为受基底（0001）滑移控制。(C)2010爱思唯尔有限公司版权所有。
The deformation behavior of an Mg89Zn4Y7 (at.%) extruded alloy composed mostly of the long-period stacking ordered (LPSO) phases, was investigated at room temperature. Several heat-treatments were conducted for the extruded alloy in the temperature range between 400 and 525 degrees C, and the correlation between the microstructure and the mechanical properties were quantitatively examined. The yield stress of the as-extruded alloy showed extremely high value of similar to 480 MPa. The deformation of the as-extruded alloy proceeded accompanied by the formation of deformation kinks and small amounts of non-basal slips. The microstructure of the extruded alloy was highly thermally stable and the yield stress showed little change by heat-treatments below 400 degrees C. However, the yield stress was gradually decreased by annealing above 400 degrees C. The yield stress of the alloys annealed at and above 475 degrees C showed discontinuous decreases with increasing annealing temperature. The yield stress of the annealed specimens could be estimated by the Hall-Petch relationship by regarding the length of the long-axis of plate-like grains as the grain size. This suggests that the basal (0001) slip governed the plastic behavior of the LPSO-phase alloy composed of randomly oriented grains. (C) 2010 Elsevier Ltd. All rights reserved.