期刊
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
卷 60, 期 1, 页码 84-103出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.jmps.2011.09.010
关键词
Microstructures; Dislocations; Nucleation
资金
- Sandia Corporation (a wholly owned subsidiary of Lockheed Martin Corporation)
- U.S. Department of Energy [DE-AC04-94AL85000]
- National Science Foundation
- NSF [DMR-0748267]
- Los Alamos National Laboratories through LDRD-DR
- Division Of Materials Research
- Direct For Mathematical & Physical Scien [0748267] Funding Source: National Science Foundation
The strength of true metallic nanowires and nanopillars (diameters below 100 nm) is known to be higher than the strength of bulk metals and is most likely controlled by dislocation nucleation from free surfaces. Dislocation nucleation is a thermally activated process that is sensitive to both temperature and strain rate. However, most simulations rely on high strain rate molecular dynamics to investigate strength and nucleation, which is limited by short molecular dynamics time scales. In this work, the energetics of dislocation nucleation in gold nanowires are computed using atomistic simulations, and transition state theory is used to estimate the strength at experimental strain rates revealing detailed information outside the realm accessible to molecular dynamics simulations. This allows investigation into the competition between thermally activated dislocation nucleation and other failure mechanisms such as elastic and structural instabilities. Additionally, the mechanisms of dislocation nucleation are compared against analytical continuum models which allow a better understanding of the nucleation process including the effects of the wire surfaces. This study helps clarify and consolidate our understanding of the nature of dislocation nucleation in small structures. (C) 2011 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据