郑勇刚
开通时间:..
最后更新时间:..
点击次数:
论文类型:期刊论文
发表时间:2009-01-01
发表刊物:INTERNATIONAL JOURNAL FOR MULTISCALE COMPUTATIONAL ENGINEERING
收录刊物:SCIE、EI、Scopus
卷号:7
期号:3
页面范围:205-215
ISSN号:1543-1649
关键字:nanowire; plastic deformation; instability; fivefold deformation twin; molecular dynamics simulation
摘要:Using molecular dynamics simulations and the embedded-atom method, the bending deformation and stability of copper nanowires are investigated in this article. It is found that the plastic deformation is mainly accommodated by the propagation of and the interaction between partial dislocations nucleated from surfaces, with twinning being a very common deformation mode. Simulation results also show that the copper nanowires exhibit a decrease of resistance against plastic deformation and tend to become homogeneous with the increase of the length, while the resistance increases with the increase of the thickness under bending. These results are consistent with those from the instability analysis based on the local Hessian matrix and suggest that the structure identification method based on the Voronoi construction can be used as a reasonable criterion for instability analysis. In addition, it is also found that two- and three-conjoint fivefold deformation twins can be formed in the quasi one-dimensional nanostructures due to the abundance of partial dislocations, stacking faults, and twins.