Plasticity and structural instability in a bulk metallic glass deformed in the supercooled liquid region
Plasticity and structural instability in a bulk metallic glass deformed in the supercooled liquid region
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DOI：
10.1016/s1359-6454(01)00218-x
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发表时间：
2001-09-03
期刊：
影响因子：
9.4
通讯作者：
Hirotsu, Y
中科院分区：
文献类型：
--
作者：
Nieh, TG;Wadsworth, J;Hirotsu, Y
研究了块体非晶合金Zr-10Al-5Ti-17.9Cu-14.6Ni在过冷液中的变形行为，发现合金在低应变速率下表现为牛顿行为，在高应变速率下表现为非牛顿行为。利用X射线衍射仪和高分辨电子显微镜对非晶态材料变形前后的结构进行了分析。实验结果表明，在变形的样品中存在纳米晶，这表明非牛顿行为与变形过程中非晶态结构的同时晶化有关；即，正在测试结晶-非晶态混合结构。建立了一个基于结构演化的力学模型来解释观察到的非牛顿行为。(C)爱思唯尔科学有限公司出版的2001 Acta Materialia Inc.保留所有权利。
The deformation behavior of a bulk amorphous Zr-10Al-5Ti-17.9Cu-14.6Ni alloy was characterized in the supercooled liquid re.-ion, The alloy was observed to exhibit Newtonian behavior at low strain rates but to become non-Newtonian at high strain rates. Structures of the amorphous material, both before and after deformation, were examined using X-ray diffraction and high-resolution electron microscopy. Experimental results showed the presence of nanocrystallites in the deformed samples, suggesting that the non-Newtonian behavior,vas associated with the concurrent crystallization of the amorphous structure during deformation; that is, a mixed crystalline-plus-amorphous structure was being tested. A mechanistic model based upon structural evolution has been developed to interpret the observed non-Newtonian behavior. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.