On the tensile behavior of carbon nanotubes and nanotube-reinforced composites at large strains

In this paper, the nonlinear tensile behavior of single-walled carbon nanotubes and also carbon nanotube-reinforced composites is investigated indetail based on the equivalent continuum approach using nonlinear finite element method (FEM). The behavior of an isolated carbon nanotube is first simulated by using a progressive fracture model based on the modified Morse inter-atomic potential. Then, considering a representative volume element (RVE), the large strain tensile behavior of unidirectional nanotube-reinforced polymer composites is investigated in a rigorousapproach. In this work based on a rational approach, analytical expressions for the strain dependent elastic modulus of carbon nanotubes andthe nano-composites in the large strain unidirectional tension are presented. It is noted that a similar work exists in the literature (Tserpes et al., 2008, Theoretical and Applied Fracture Mechanics, V49, 51-60). But, some fundamental inconsistencies in the nonlinear analysis of that work are observed. Also, the method of derivation of the strain dependent elastic modulus is incorrect. The aim of this work is the analysis in a consistentand rigorous approach for deriving correct results

Keywords:

Carbon Nanotube , Large Strains , Nonlinear Finite Element Method , TensileBehavior