Study of Aspect Ratio Effect on Mechanical Properties Polymer/NanoComposite

Document Type : Persian

Authors

1 M.Sc. Student, Shahrekord University

2 Associate Professor, Faculty of Engineering, Shahrekord University

3 Assistant Professor, Department of Mechanical Engineering, Esfahan University of Technology

Abstract

Carbon nanotubes (CNTs) demonstrate unusually high stiffness, strength and resilience, and are therefore an ideal reinforcing material for nanocomposites. However, much work has to be done before the potentials of CNT-based composites can be fully realized.  Evaluating the effective material properties of such nanoscale materials is a very difficult tasks.  Simulations using molecular dynamics and continuum mechanics models can play significant roles in this development. Currently, the continuum approach seems to be the only feasible approach for such large scale analysis. In this paper, effective mechanical properties of CNT-based composites are evaluated using a square representative volume element (RVE) based on the continuum mechanics and Finite Element Method (FEM).  Formulas are derived based on the elasticity theory to extract the effective material constants from solutions for the square RVEs under two load cases.  Next, CNT aspect ratio effects on the nanocomposite mechanical properties are investigated. Results indicate that increasing CNT aspect ratio results in an increase in nanocomposite longitudinal modulus and a decrease in nanocomposite transverse modulus. Also, increasing the CNT aspect ratio resulted in a decrease in nanocomposite Poisson’s ratio in the x-y plane and an increase in nanocomposite Poisson’s ratio in the x-z plane.

Keywords

References

1] Iijima S., Helical Microtubes of Graphitic Carbon, Nature (London), 354, 1991, pp. 56-58.
[2] Liu Y., Nishimura N., d Otani Y., Large-scale modeling of carbon-nanotube composites by a fast multiple boundary element method, Computational Materials Science, 34, 2005, pp. 173-187.
[3] Thostenson E.T., Chunyu L., Chou T.W., Nanocomposites in context, Composites science and Technology, 65, 2004, pp. 491-516.
[4] Golestanian H., Shojaie M., Numerical characterization of VNT-based polymer composites considering interface, Computational Material Science, 50, 2010, pp. 731-736.
[5] Matin Ghahfarokhi Z., Golestanian H., Effects of nanotube helical angle on mechanical properties of carbon nanotube reinforced polymer composites, Computational Material Science, 50, 2011, pp. 3171–3177.
[6] Liu J., Chen X.l., Evaluation of the effective material properties of carbon nanotube-based composites using a nanoscale representative volume element, Mechanics of Materials, 35, 2003, pp. 69-81.
[7] Florian H.G., Wichmann M., Fiedler B., Schulte K., Influence of different carbon nanotubes on the mechanical properties of epoxy matrix composites – A comparative study, Composite Science and technology, 65, 2005, pp. 2300–2313.
[8] Cornwell C.F., Wille L.T., Elastic Properties of single-walled carbon nanotubes in compression, Solid State Communication, 101, 1997, pp. 555-558.
[9] Gao G.H., Cagin T., Goddard W.A., Energetic, structure, mechanical and vibrational properties of single-walled carbon nanotubes, Nanotechnology, 9, 1998, pp. 187-191.
[10] Nardelli M.B., Fattebert J.L., Mechanical properties, defects and electronic behavior of carbon nanotubes, Carbon, 38, 2000, pp. 1703-1711.
[11] Wong E.W., Sheehan P.E., Lieber C.M., Nanobeam mechanics: Elasticity, strength and toughness of nanorods and nanotubes, Science, 227, 1997, pp. 1971-1975.
[12] Ruoff R., Lorents D.C., Mechanical and thermal properties of carbon nanotubes, Carbon, 33, 1995, pp. 925-930.
[13] Salvetat J.P., Bonard J.M., Thomson N.H., Kulik A.J., Mechanical properties of carbon nanotubes, Applied Physics A-Materials Science and Processing , 69, 1999, pp. 225-260.
 
Journal of Simulation and Analysis of Novel Technologies in Mechanical Engineering
Volume 4, Issue 1 - Serial Number 1
September 2011
Pages 27-34

Files

Share

How to cite

Statistics