Effective method for investigation of buckling behavior of carbon nanotubes

Results of studies carried out by Iranian researchers from Gilan University led to the presentation of a reliable and precise mathematical method of studying mechanical behavior of carbon nanotubes, which is independent from Young’s modulus and thickness of nanotubes. The presented method can help the designing of products based on carbon nanotubes. Carbon nanotubes are among the most important major parts in the production of nanoelectro-mechanical devices due to their unique properties. When a thin structure such as carbon nanotube used in a nanoelectro-mechanical system is subjected to pressure load, a type of instability called buckling appears in the structure. Therefore, it is very important to study their mechanical behavior. Results showed that continuous classic models predict the critical load higher than the actual amount. As the scale factor increases, critical load decreases in the nanotube. It means the toughness of nanotubes decreases taking into account the effects of scale. The effect of geometry on the stability of nanotube was studied too. It was shown that when the geometric parameter of the ratio of length to diameter increases, or in other words, when the nanotube becomes narrower, scale down has less effects on the critical load due to the high length of the tube in comparison with its internal characteristic length such as bond length. It was also observed that wave number had a great effect on the importance of scale effects on the stability of nanotube. The researchers will continue the research and they will use the presented method in this research to analyze other mechanical phenomena, including vibrations and flexural behavior in other nanostructures such as nanosheets and nanocones. Results of the research have been published in details in Composite Structures, vol. 100, January 2013, pp. 323-331. This article is considered as one of the top articles approved by Iran Nanotechnology Initiative Council.