A multiscale approach for estimating the chirality effects in carbon nanotube reinforced composites

In this paper, the multiscale representative volume element approach is proposed for modeling the elastic behavior of carbon nanotubes reinforced composites. The representative volume element incorporates the continuum approach, while carbon nanotube characterizes the atomistic approach. Space frame structure similar to three dimensional beams and point masses are employed to simulate the discrete geometrical constitution of the single walled carbon nanotube. The covalent bonds between carbon atoms found in the hexagonal lattices are assigned elastic properties using beam elements. The point masses applied on each node are coinciding with the carbon atoms work as mass of beam elements. The matrix phase is modeled as a continuum medium using solid elements. These two regions are interconnected by interfacial zone using beam elements. Analysis of nanocomposites having single walled carbon nanotube with different chiralities is performed, using an atomistic finite element model based on a molecular structural mechanics approach. Using the proposed multi scale model, the deformations obtained from the simulations are used to predict the elastic and shear moduli of the nanocomposites. A significant enhancement in the stiffness of the nanocomposites is observed. The effects of interfacial shear strength, stiffness, tensile strength, chirality, length of carbon nanotube, material of matrix, types of representative volume elements and types of loading conditions on the mechanical behavior of the nanocomposites are estimated. The finite element results are compared with the rule of mixtures using formulae. It is found that the results offered by proposed model, are in close proximity with those obtained by the rule of mixtures.

The multiscale representative volume element approach is proposed for modeling the elastic behavior of carbon nanotubes reinforced composites. The deformations obtained from the simulations are used to predict the elastic and shear moduli of the nanocomposites.Figure optionsDownload as PowerPoint slideHighlights
► Multiscale representative volume element approach is proposed for modeling the elastic behavior of carbon nanotubes reinforced composites.
► The matrix phase is modeled as a continuum medium using solid elements.
► The two regions are interconnected by interfacial zone using beam elements.
► Analysis of nanocomposites is performed, using an atomistic finite element model based on a molecular structural mechanics approach.
► The effects of different elastic properties, chirality, length of CNT, material of matrix, types of RVE and types of loading conditions applied to nanocomposites are estimated.