0
Research Paper

Effect of Pinhole Defects on the Elasticity of Carbon Nanotube Based Nanocomposites

[+] Author and Article Information
Unnati A. Joshi

Department of Mechanical and Industrial Engineering, Vibration and Noise Control Laboratory, Indian Institute of Technology Roorkee, Roorkee 247667, Indiaunnatiajoshi@gmail.com

Satish C. Sharma

Department of Mechanical and Industrial Engineering, Vibration and Noise Control Laboratory, Indian Institute of Technology Roorkee, Roorkee 247667, Indiasshmefme@iitr.ernet.in

S. P. Harsha

Department of Mechanical and Industrial Engineering, Vibration and Noise Control Laboratory, Indian Institute of Technology Roorkee, Roorkee 247667, Indiasurajfme@iitr.ernet.in

J. Nanotechnol. Eng. Med 2(1), 011003 (Jan 04, 2011) (7 pages) doi:10.1115/1.4003028 History: Received September 29, 2010; Revised December 12, 2010; Published January 04, 2011; Online January 04, 2011

Carbon nanotubes (CNTs) have been regarded as an ideal reinforcements of high-performance composites with enormous applications. In this paper, the effects of pinhole defect are investigated for carbon nanotube based nanocomposites using a 3D representative volume element (RVE) with long CNTs. The CNT is modeled as a continuum hollow cylindrical shape elastic material with pinholes in it. These defects are considered on the single wall (CNTs). The mechanical properties such as Young’s modulus of elasticity are evaluated for various pinhole locations and number of defects. The influence of the pinhole defects on the nanocomposite is studied under an axial load condition. Numerical equations are used to extract the effective material properties for the different geometries of RVEs with nondefective CNTs. The field-emission microscopy (FEM) results obtained for nondefective CNTs are consistent with the analytical results for cylindrical RVEs, which validate the proposed model. It is observed that the presence of pinhole defects significantly reduces the effective reinforcement when compared with nondefective nanotubes, and this reinforcement decreases with the increase in the number of pinhole defects. It is also found from the simulation results that the geometry of RVE does not have much significance on the stiffness of nanocomposites.

Copyright © 2010 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

(a) Schematic view of a single pinhole defect model. Type-1: defect of six atoms. (b) Schematic view of a single pinhole defect model. Type-2: defect of 24 atoms.

Grahic Jump Location
Figure 2

Layout of the defects: (a) single defect, (b) three defects, (c) five defects, and (d) seven defects

Grahic Jump Location
Figure 3

(a) Sketch of CNT based cylindrical RVE under an axial pull. (b) Sketch of CNT based hexagonal RVE under an axial load.

Grahic Jump Location
Figure 4

Stress distribution pattern for cylindrical RVE with 11 pinhole defects type-2

Grahic Jump Location
Figure 5

Deformation of composite with hexagonal RVE having five pinhole defects type-1 under axial stretch.

Grahic Jump Location
Figure 6

Maximum principle stress pattern for hexagonal RVE with seven pinhole defects type-2

Grahic Jump Location
Figure 7

Graph presenting elasticity moduli of nanocomposite with cylindrical RVE to validate the FEM model with Halpin–Tsai model

Grahic Jump Location
Figure 8

Comparison between nondefective and defective CNTs for cylindrical RVE against different ratios of Et/Em

Grahic Jump Location
Figure 9

Effect of changing the location of pinhole defect on Young’s modulus of elasticity for cylindrical RVE

Grahic Jump Location
Figure 10

Comparison between results of current FEM model and model of Hirai (15) for tensile stiffness

Grahic Jump Location
Figure 11

Trend showing effective elasticity modulus for cylindrical RVE with pinhole type-1 and type-2

Grahic Jump Location
Figure 12

Comparison between nondefective and defective CNTs for hexagonal RVE against different ratios of Et/Em

Grahic Jump Location
Figure 13

Effect of the number of pinhole defects on effective modulus of elasticity for hexagonal RVE

Grahic Jump Location
Figure 14

Column chart presentation of modulus of elasticity for nanocomposite with pinhole type-2 and hexagonal RVE

Grahic Jump Location
Figure 15

Comparison between modulus of elasticity values of cylindrical and hexagonal RVEs

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In