| | Various experimental and theoretical investigations have been carried out to determine the elastic properties of nanotubes in the axial direction. Their behavior in transverse directions, however, has not been well studied. In this work, a combination of molecular dynamics (MD) and continuum-based elasticity model is used to predict the transverse-isotropic elastic properties of single-walled carbon nanotubes (SWCNTs). From this modeling study, five independent elastic constants of an SWCNT in transverse directions are obtained by analyzing its deformations under four different loading conditions, namely, axial tension, torsion, uniform and non-uniform radial pressure. To find the elastic constants in the transverse directions, the strain energy due to radial pressure is calculated from the MD simulation. Then, a continuum-based model is implemented to find the relation between the strain energy and maximum pressure under these two loading conditions. Based on the energy equivalence between the MD simulation and the continuum-based model, the transverse-isotropic elastic constants of SWCNTs are computed. These constants are then used in an FEM-based simulation to investigate the effect of SWCNT orientation on the shear modulus of nanocomposites. Furthermore, shear stress distributions along the nanotube axis and over its cross-sectional area are investigated to study the effect of CNT orientation on the shear load transfer.
Seminar Speaker:
Dr. Abbas Montazeri
Date :
7 Feb. 2013
Time :
11:00 - 12:30
| |
|
