| 引用本文: | 陈晶晶,翁盛槟,吴昊.基于球面触点接触模式的铜膜纳观变形探析∗[J].中国表面工程,2021,34(4):99~106 |
| CHEN Jingjing,WENG Shengbin,WU Hao.Effects of Mechanism Analysis for Spherical Contact Pair on Contact Deformation in Copper Film from Nano-perspective∗[J].China Surface Engineering,2021,34(4):99~106 |
|
| 摘要: |
| 对微机电系统金属铜膜接触变形特征的了解和位错原子迁演的寻迹对改善工况接触质量极为重要。 基于分子动力学法,对球面触点与微器件铜膜的接触变形展开研究,分析铜膜力-位移曲线对应构型演变特征,用 WSDA 法描述接触变形特性,并比对触点轮廓对铜膜内、外表面的变形差异。 研究表明:弹性接触时,力-位移曲线的 Hertz 理论与 MD 结果吻合,而接触区铜膜两侧的位错环凸显是塑性变形始发源与侧面滑移带产生的萌芽端,也是弹性阶段后的 Hertz 理论与 MD 的力-位移曲线不吻合主因。 受载铜膜的位错原子会演化为位错环,位错环构型演变有 4 个动态阶段:位错环萌芽期、生长增大期、繁衍增殖期、维持稳定期。 随着触点轮廓增加,位错环构型也相应扩张,而位错环演化 4 个阶段不受外围轮廓影响。 另外,受载铜膜接触区两侧滑移带蔓延处的应力较集中,亚表层应力集中度强烈依赖于触点外围轮廓尺寸。 验证了 WSDA 法可有效描述铜膜受载时的变形特征,并随触点轮廓增加而迅速向两侧蔓延传播,与受载铜膜的应力、应变趋势获得一致。 研究结果将对微观金属弹塑性变形转化的微观临界态揭示中有着重要参鉴价值。 |
| 关键词: 弹塑性临界态 球面接触副 位错演化 原子模拟 位错环 |
| DOI：10.11933/j.issn.1007-9289.20210318001 |
| 分类号:TG156;TB114 |
| 基金项目:福建省自然科学基金(2017J01709, 2018J01509, 2018J01556)、宁德师范学院重大科研培育 (2017ZDK19) 和 2017 年福建省互联网+大学生创新创业省级教育(闽教学[2017] 52 号)资助项目 |
|
| Effects of Mechanism Analysis for Spherical Contact Pair on Contact Deformation in Copper Film from Nano-perspective∗ |
|
CHEN Jingjing1, WENG Shengbin2, WU Hao3
|
|
1.School of Information and Mechatronics Engineering,Ningde Normal University, Ningde 352100 , China;2.Engineering Training Center, Quzhou University, Quzhou 324000 , China;3.Beijing Institute of Space Launch Technology, Beijing 100048 , China
|
| Abstract: |
| To insight the underlying deformation for micro devices in micro / nano electrical mechanical system ( MEMS / NEMS) is extremely important. However, a few research was reported on the evolution of copper deformation and the explore of dislocation atomic migration rules at atomic level. Therefore, the correlated understand work for them behaviour and mechanism were studied. The configuration evolution for dislocation atoms, and the curve characteristic of force vs displacement were analyzed. Wigner-seitz defect analysis (WSDA) method was proposed to describe this effect of spherical contact pair with different contour on them deformation. It was showed that the force vs displacement curve obtained consistent by comparing Hertz theory with molecular dynamics (MD) result at elastic stage. Furthermore, the dislocation loop was found as the original source of plastic deformation, it was the main reason to lead the curve of force vs displacement is not inconsistency after elastic deformation. An interesting phenomena was demonstrated on dislocation loop evolution process, which experienced four stages during loading, namely formal stage, growth stage, reproduction stage, maintenance stage. This external configuration features for dislocation ring evolution shows expand as curvature contour increase. Nevertheless, all above four stages are not affected by them increase. In addition, it is serious than other places in subsurface deformation at loading. The WSDA method was applied to describe their defect characteristics, this result shows that the propagationroute can spreads to sides rapidly as contour increase, which is consistent with changes of stress and strain trend. This research result plays a significance role in understanding the underlying mechanism on its elastic-plastic deformation. . |
| Key words: elastic-plastic critical state spherical contact pair dislocation evolution atomic simulation plastic loop |
