Computational modelling of carbon nanotube reinforced polymer composites

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.


Investigating the mechanical properties of single walled carbon nanotube reinforced epoxy composite through finite element modelling
Zuberi, Muhammad Jibran Shahzad; Esat, Volkan (2015-03-15)
Varying experimental results on the mechanical properties of carbon nanotube reinforced polymer composites (CNTRPs) have been reported due to the complexities associated with the characterization of material properties in nano-scale. Insight into the issues associated with CNTRPs may be brought through computational techniques time- and cost-effectively. In this study, finite element models are generated in which single walled carbon nanotube models are embedded into the epoxy resin. For modelling interface...
Theoretical prediction of bulk glass forming ability (BGFA) of Ti-Cu based multicomponent alloys
SUER, Sila; Mehrabov, Amdulla; Akdeniz, Mahmut Vedat (Elsevier BV, 2009-03-01)
The bulk glass forming ability (BGFA) of Ti-Cu based multicomponent alloys has been evaluated via theoretical modeling and computer simulation studies based on a combination of electronic theory of alloys in the pseudopotential approximation and the statistical thermodynamical theory of liquid alloys The. magnitude of atomic ordering energies, calculated by means of the electronic theory of alloys in the pseudopotential approximation, was subsequently used for calculation of the key thermodynamic parameters...
Evaluating the effects of size and chirality on the mechanical properties of single-walled carbon nanotubes through equivalent-continuum modelling
Zuberi, M. Jibran S.; Esat, Volkan (2016-10-01)
Due to numerous difficulties associated with the experimental investigation of the single-walled carbon nanotubes (SWNTs), computational modelling is considered to be a powerful alternative in order to determine their mechanical properties. In this study, a novel three-dimensional finite element model incorporating a beam element with circular cross section is developed based on equivalent-continuum mechanics approach. The beam elements are used as the replacement of C-C chemical bonds in modelling SWNTs. F...
Micromechanical Modelling of Carbon Nanotube Reinforced Composite Materials with a Functionally Graded Interphase
Gülaşık, Hasan; Göktepe, Serdar; Gürses, Ercan (null; 2018-10-10)
This paper introduces a new method of determining the mechanical properties of carbon nanotube-polymer composites using a multi-inclusion micromechanical model with functionally graded phases. The nanocomposite was divided into four regions of distinct mechanical properties; the carbon nanotube, the interface, the interphase and bulk polymer. The carbon nanotube and the interface were later combined into one effective fiber using a finite element model. The interphase was modelled in a functionally graded m...
A theoretical study of chemical doping and width effect on zigzag graphene nanoribbons
Pekoz, Rengin; Erkoç, Şakir (Elsevier BV, 2009-12-01)
The energetics and the electronic properties of nitrogen- and boron-doped graphene nanoribbons with zigzag edges have been investigated using density functional theory calculations. For the optimized geometry configurations, vibrational frequency analysis and wavefunction stability tests have been carried out. Different doping site optimizations for a model nanoribbon have been performed and formation energy values of these sites revealed that zigzag edgesite for both of the dopants were the most favorable ...
Citation Formats
M. J. S. Zuberi, “Computational modelling of carbon nanotube reinforced polymer composites,” M.S. - Master of Science, Middle East Technical University, 2014.