Vali Parvaneh - Department of Mechanical Engineering, Shahrood University of Technology, Daneshgah Blvd, Shahrood
Amir Masood Majd Sabeti
Mahmoud Shariati

Because of the high specific stiffness and strength, carbon nanotubes represent a very promising material as reinforcements in composite materials.At present, there is a great deal of debate on the thickness of the transition layer, i.e. the equilibrium distance between the polymer chain and nanotube.In the first consideration, some researchers advocated that there is no chemical bond between the nanotube and polymer. Therefore, only non-bonded potentials from electrostatic and van der Waal’s forces are considered. Several numerical models have been developed with this approach. These studies are based on micromechanics models, since atomistic models are too computationally demanding for CNT nanocomposites. Odegard et al. [1] developed a Representative Volume Element (RVE) with an equivalent-continuum model (truss element based) of the composite material based on the equilibrium molecular structure obtained with the MD simulations.Usually at the interface between the CNTs and the polymer there is just a van der Waals interaction that is able to produce only a weak normal forces and almost null shear strength, as investigated by Frankland et al. [2](second consideration). In their work the shear strength at the interface between a single-walled nanotube and a polymer matrix, with or without covalent bonds, was computed using molecular dynamics simulations.Odegard et al.[1] and hu et al.[3] have been used truss model and beam model for carbon nanotube respectively. In present work, we are used a spring model that are analyzed by ABAQUS software. Take a few time for modeling and analyzing, accuracy in results and also nonlinearity of elements between carbon atoms are superiority of this model to other models