Numerical investigation on mechanical properties of graphene covering silicon nanofilms

作者:Tang, Yunqing; Yang, Bing; Yang, Haiying; Yang, Ping*; Yang, Jianming; Hu, Yongle
来源:Computational Materials Science, 2017, 126: 321-325.
DOI:10.1016/j.commatsci.2016.09.031

摘要

The aim of this article is to perform an evaluation on mechanical properties of graphene covering silicon nanofilms by using molecular dynamics calculations. The deformation process of the composite film is simulated under uniaxial tensile loading to demonstrate the structural evolution, and the structural failure mode is discussed considering various film thicknesses and temperatures. The results show that size effect of thickness on the strength is significant at the thickness less than 4 nm and thinner thickness can help improve tensile properties of the nanofim. The 1 nm thick film has significantly better mechanical properties due to its different structural failure mode, and the substrate silicon is the weakness which limits mechanical properties of the composite film under high temperatures. It is hoped that our findings will be helpful for applications of graphene in silicon-based devices and materials.