Reveal the size effect on the plasticity of ultra-small sized Ag nanowires with in situ atomic-scale microscopy
Reveal the size effect on the plasticity of ultra-small sized Ag nanowires with in situ atomic-scale microscopy
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利用原位原子尺度显微镜揭示超小尺寸银纳米线可塑性的尺寸效应
DOI：
10.1016/j.jallcom.2016.03.199
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发表时间：
2016-08-15
影响因子：
6.2
通讯作者：
Han, Xiaodong
中科院分区：
文献类型：
--
作者：
Kong, Deli;Sun, Shiduo;Han, Xiaodong
揭示金属纳米线的原子尺度形变机制对金属纳米线的实际应用具有重要意义。然而，很少有报道提供直接的原子尺度上的实验解释这些金属纳米线。在这里，我们进行了一系列的原位变形测试银（Ag）纳米线的直径为3-11 nm。原位原子尺度的观察揭示了一个过渡的变形机制与Ag纳米线的直径减小。对于直径约为11 nm的[5（5）over bar 4]和[001]取向的纳米线，其塑性变形主要是由包含前导和拖尾部分位错的全位错控制的，而直径约为5-8 nm的纳米线中很少观察到全位错或扩展位错，其塑性变形主要由SF的产生和湮灭控制。此外，对于[（1）over bar 11]取向的纳米线，当直径约为5 nm时，经常观察到60度混合和纯刃位错，并且对于直径小于约3 nm的纳米线，塑性变形通过两个相邻{111}面之间的相对滑移来调节。这些结果表明，塑性变形不仅取决于纳米线的大小，但也可以显着影响加载方向。(C)2016爱思唯尔B. V.保留所有权利。
Revealing the atomic-scale deformation mechanisms of metallic nanowires (NWs) is important for their practical application. However, there are few reports providing direct atomic-scale experimental elucidation on those metallic NWs. Here, we conduct serial in situ deformation tests on silver (Ag) nanowires with diameters of 3-11 nm. The in situ atomic-scale observations reveal a transition in the deformation mechanism with a decrease in the diameter of Ag NWs. For the [5 (5) over bar4] and [001] oriented NWs with diameters of similar to 11 nm, the plastic deformation is dominated by full dislocation that involves leading and trailing partial dislocations, whereas the full or extended dislocations are rarely observed in the NWs with diameters in the range of similar to 5-8 nm, and their plastic deformation is governed by SF generation and annihilation. Moreover, for the [(1) over bar 11] oriented NWs, 60 degrees mixed and pure edge dislocations are frequently observed when the diameter is approximately 5 nm and the plastic deformation is accommodated by relative slip between two adjacent {111} planes for NWs with diameters below similar to 3 nm. These results indicate that the plastic deformation not only depends on the size of NWs but also can be significantly impacted by the loading orientation. (C) 2016 Elsevier B.V. All rights reserved.