標題: Characterizing the fracture parameters of a graphene sheet using atomistic simulation and continuum mechanics
作者: Tsai, Jia-Lin
Tzeng, Shi-Hua
Tzou, Yu-Jen
機械工程學系
Department of Mechanical Engineering
關鍵字: Graphene sheet;Fracture;Strain energy release rate;Molecular dynamics simulation
公開日期: 1-二月-2010
摘要: The fracture behavior of a graphene sheet, containing a center crack (length of 2a) was characterized based on the atomistic simulation and the concept of continuum mechanics. Two failure modes, i.e., opening mode (Mode I) and sliding mode (Mode II), were considered by applying remote tensile and shear loading, respectively, on the graphene sheet. In the atomistic simulation, the equilibrium configurations of the cracked graphene subjected to applied loadings, before and after the crack extension of 2 Delta a, were determined through molecular dynamics (MD) simulation, from which the variation of the potential energy and the strain energy release rate of the discrete graphene sheet because of crack extension was calculated accordingly. It is noted that because of the discrete attribute, there is no stress singularity near the crack tip, and thus, the concept of stress intensity factor that is generally employed in the continuum mechanics may not be suitable for modeling the crack behavior in the atomistic structures. For the sake of comparison, the continuum finite element model with the same geometric parameters and material properties as the atomistic graphene sheet was constructed, and the corresponding strain energy release rate was calculated from the crack closure method. Results indicated that the strain energy release rates obtained from the continuum model exhibit good agreement with those derived from discrete atomistic model. Therefore, it is suggested that the strain energy release rate is an appropriate parameter, which can be employed in the atomistic model and the continuum model for describing the fracture of covalently bonded graphene sheet. (C) 2009 Elsevier Ltd. All rights reserved.
URI: http://dx.doi.org/10.1016/j.ijsolstr.2009.10.017
http://hdl.handle.net/11536/5934
ISSN: 0020-7683
DOI: 10.1016/j.ijsolstr.2009.10.017
期刊: INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
Volume: 47
Issue: 3-4
起始頁: 503
結束頁: 509
顯示於類別:期刊論文


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  1. 000274078100014.pdf