Structural vibration analysis of single walled carbon nanotubes with atom-vacancies

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2010

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Doğan, İbrahim Onur

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Recent investigations in nanotechnology show that carbon nanotubes (CNT) have one of the most significant mechanical, electrical and optical properties. Interactions between those areas like electrical, optical and mechanical properties are also very promising in both research and industrial fields. Those unique characteristics are built by mainly the atomistic structure of the carbon nanotubes. In this thesis, the effects of vacant atoms on single walled carbon nanotubes (SWCNT) are investigated using matrix stiffness method. In order to use this technique a linkage between structural mechanics and molecular mechanics is established. A code has been developed to construct the SWCNT with the desired chirality, extracting the vacant atoms with the corresponding atomic bonds between the neighbor nodes and calculating the effect of those vacancies on its vibrational properties. A finite element software is also utilized for validation of the code and results. In order to investigate the convergence of the effect of those vacant nodes a numerous number of analyses have been carried out with randomly positioned vacant atoms. Also consecutive vacant nodes have been positioned in order to investigate the effect on the structural properties through the length of a CNT. In addition to those, as a case study, the reduction in Young's modulus property because of the vacancies has also been investigated and the effects are tabulated in the report. It is concluded in this study that the any amount of vacant atoms have substantial effect on modal frequencies and Young's modulus. Chirality and the position of the vacancies are the main parameters determining the structural properties of a CNT.

Subject Keywords

Mechanical engineering., Vibration.

URI

http://etd.lib.metu.edu.tr/upload/3/12611550/index.pdf
https://hdl.handle.net/11511/19291

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

İ. O. Doğan, “Structural vibration analysis of single walled carbon nanotubes with atom-vacancies,” M.S. - Master of Science, Middle East Technical University, 2010.