Computational modelling of carbon nanotube reinforced polymer composites

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2014-7
Zuberi, Muhammad Jibran Shahzad
This thesis investigates the effects of chirality and size of single-walled carbon nanotubes (SWNTs) on the mechanical properties of both SWNTs and carbon nanotube reinforced epoxy composites (CNTRPs). First, a novel 3D beam element finite element model is developed based on equivalent-continuum mechanics approach and used for replacing C-C chemical bond for modelling SWNTs. The effects of diameter and chirality on the Young’s moduli, shear moduli, shear strains and Poisson’s ratios of SWNTs are studied. For modelling CNTRPs, the aforementioned SWNTs are embedded into the epoxy resin finite element model. The volume fraction of SWNTs in epoxy is taken as 5% while the diameter for interface region between the two phases is taken twice to that of the SWNTs. For modelling interface regions, two approaches named as non-bonded interactions model and perfect bonding model are used and compared against each other. The latter approach is employed for evaluating the effects of chirality and size of SWNTs on the Young’s modulus and Poisson’s ratio of CNTRPs. The results for Young’s moduli are in good agreement with those calculated by a theoretical relation known as continuum rule of mixtures. In order to quantify the structural mass reduction by using these CNTRPs for a particular application, specific strength is calculated for both pure epoxy resin and the composite. Result shows that the structural mass can be reduced 5 times compared to that of epoxy if its nanocomposite is used in its potential applications where the strength and volume requirements are fixed such as parts for automobiles and aircrafts. This mass reduction will ultimately lead towards better mileage, fuel savings and reduction in carbon emissions.

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Citation Formats
M. J. S. Zuberi, “Computational modelling of carbon nanotube reinforced polymer composites,” M.S. - Master of Science, Middle East Technical University, 2014.