Study of Aspect Ratio Effect on Mechanical Properties Polymer/NanoComposite

Journal of Simulation and Analysis of Novel Technologies in Mechanical Engineering

مقاله 4، دوره 4، شماره 1، آذر 2011، صفحه 27-34   

نوع مقاله: Persian

نویسندگان

Mohamad Hashemi Gahruei¹؛ Hossein Golestanian^{* 2}؛ Mehdi Salmani Tehrani³

¹M.Sc. Student, Shahrekord University

²Associate Professor, Faculty of Engineering, Shahrekord University

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

چکیده

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.

کلیدواژه‌ها

nanocomposite؛ Carbon Nanotube؛ Aspect Ratio؛ Finite Element Analysis؛ Mechanical Properties

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