Nanotechnology can be expressed as science and technologywhere dimensions and tolerances in the range of 0.1 nanometer (nm) to 100 nmplay a critical role. Nanotechnology involves detailed engineering works inthe areas of 1) Nanomechanical engineering (the study of molecular machines) 2)Nanoelectrical engineering (it involves nanometer scale electronic systems) 3)complex systems like the assemblers, replicators and nano computers (Tomanufacture a desired material with precise atomic placement).


Carbon Nano Tube


One of the important materials that were developed in nanomaterials is carbon nano tube. Carbon nanotubes were discovered in 1991 as aminor by-product of fullerene synthesis. It is a dichotomy that Carbon nanotubes being thesmallest of all tubes are strongest and stiffest materials on earth, they alsohave a very high surface area to volume ratio. This strength results from thecovalent sp bonds formed between the individual carbon atoms. Multi-walledcarbon nanotube was tested to have a tensile strength of 63 gigapascals (GPa).(This, for illustration, translates into ability to endure weight of 6300 kg on a cable with cross-section of 1 mm2.) Since carbon nanotubes have alow density for a solid of 1.3-1.4 gcm−3, &sec=article&uinfo=<%=server.URLEncode(2227)%>"title="">[17]its specificstrength of up to 48,000 kNmkg−1 is the bestof known materials, compared to high-carbon steel's 154 kNmkg−1.


Under excessive tensile strain, the tubes willundergo plastic deformation,which means the deformation is permanent. This deformation begins at strains ofapproximately 5% and can increase the maximum strain the tube undergoes beforefracture by releasing strain energy.


CNTs are not nearly as strong under compression.Because of their hollow structure and high aspect ratio, they tend to undergo buckling when placedunder compressive, torsion or bending stress.



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Theauthor is CEO ofNamo Textile Co. Pvt. Ltd