Combined influences of micro-pillar geometry and substrate constraint on microplastic behavior of compressed single-crystal micro-pillar: Two-dimensional discrete dislocation dynamics modeling
Combined influences of micro-pillar geometry and substrate constraint on microplastic behavior of compressed single-crystal micro-pillar: Two-dimensional discrete dislocation dynamics modeling
复制标题
微柱几何形状和基底约束对压缩单晶微柱微塑性行为的综合影响：二维离散位错动力学建模
DOI：
10.1016/j.msea.2009.07.037
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发表时间：
2009-11
期刊：
影响因子：
6.4
通讯作者：
Hou, Chuantao
中科院分区：
文献类型：
--
作者：
Hu, Lili;Ouyang, Chaojun;Li, Zhenhuan;Huang, Minsheng;Hou, Chuantao
采用二维离散位错动力学模拟方法，研究了巨型底座上受压微柱的尺寸效应及其微塑性行为。除了常规的微柱尺寸和高宽比等尺寸参数外，还考虑了微柱锥角和微柱内位错滑移面方位角，以解决尺寸效应及其丰富的内在机理。计算结果表明，微柱的塑性行为至少有两种作用机制。一种与微柱侧壁的无位错滑出有关，另一种与微柱底部和顶端的位错堆积有关。微柱尺寸效应的总体机制取决于微柱尺寸、高宽比、微柱锥度和滑动面方位角等多个因素，而“自由滑移带”的存在是最重要的表征。由于自由滑移带的存在，著名的施密德定律在细长的微柱中仍然有效，而在较大的微柱中，由于没有自由滑移带，它可能会失效；结果，出现了复杂的甚至“反向”的尺寸效应。
2D discrete dislocation dynamic modeling of compressed micro-pillars attached on a huge base is executed to study the size-dependent microplastic behavior of micro-pillars and the corresponding size effect. In addition to the conventional dimensional parameters of the micro-pillar such as the micro-pillar size and the height-to-width ratio, the micro-pillar taper angle and the dislocation slip plane orientation angle in the micro-pillar are also considered to address the size effect and its rich underlying mechanism. Computational results show that there are at least two operating mechanisms responsible for the plastic behavior of micro-pillars. One is associated with the dislocation free slip-out from the micro-pillar sidewall; the other is related to the dislocation pile-up at the base and the top end of the pillar. The overall mechanism governing the size effect of the micro-pillar rests with multi-factors, including the micro-pillar size, the height-to-width ratio, the micro-pillar taper and the slip plane orientation angle; however, whether the “free slip band” exists or not is the most important denotation. The well-known Schmid law still validates in the slender micro-pillars due to existence of the free slip band, whereas it may fail in the podgier micro-pillars due to absence of the free slip band; as a result, a complicated even “reverse” size effect appears.
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影响因子：
9.4
作者：
S. Rao;D. Dimiduk;T. Parthasarathy;M. Uchic;M. Tang;C. Woodward
通讯作者：
S. Rao;D. Dimiduk;T. Parthasarathy;M. Uchic;M. Tang;C. Woodward
影响因子：
8.6
作者：
Zhu, Ting;Li, Ju;Gall, Ken
通讯作者：
Gall, Ken
影响因子：
9.4
作者：
Dimiduk, DM;Uchic, MD;Parthasarathy, TA
通讯作者：
Parthasarathy, TA
DOI：
10.1016/j.msea.2005.03.082
发表时间：
2005-07-25
影响因子：
6.4
作者：
Uchic, MD;Dimiduk, DA
通讯作者：
Dimiduk, DA
影响因子：
9.4
作者：
Budiman, A. S.;Han, S. M.;Nix, W. D.
通讯作者：
Nix, W. D.