Mechanical Property Evaluation of Carbon Nanotube Sheets

The uses of carbon nanotubes (CNTs) in nanotechnology and leading industries are of extreme importance and they have many applications. One such application is producing nanotube thin pages called buckypaper. These pages, known as nanotube sheets, have signi cant physical, chemical, mechanical, thermodynamic and electromagnetic properties, such as being several times stronger than steel. In spite of e orts devoted to the development of procedures for the production of buckypaper, not many attempts have been made to understand their mechanical behavior. Computer simulations can be used as a powerful tool to discover the mechanical properties of these materials. The aim of the present research is to investigate the mechanical behavior of buckypaper using the nite element method. Toward this goal, the molecular network of buckypaper, which consists of a regular arrangement of CNTs, is modeled as a structure with its atoms as nodes, its bonds as 3-D-beam elements and Van der Waals forces by means of nonlinear forces. A computer program is then developed to calculate the mechanical properties of buckypaper especially the modulus of elasticity. In this program, the nanotubes are arranged together to create a simple ordered network with periodic boundary conditions resembling real buckypaper. The obtained results from this procedure are compared with those derived from molecular mechanics.