8/3/2019 Cabon Nano

1/26

Manufacturing Engineering

B.Tech (3rd -sem)Central Institute of Plastics Engineering and

Technology

Ahmadabad

8/3/2019 Cabon Nano

2/26

Carbon nano tubes are allotropes of carbon. Carbonnano tubes are just a few billionths of a meter across, but are ultra strong.

Their unusual properties promies to revolutionize electronics, computers,chemistry and material sciences. They had been discovered in 1991.

One of the main applications of carbon nano tubes issuper strong bullet proof vests. A new bullet proof material is designed whichactually rebounds the force of a bullet. Bulletproof materials at the momentare designed to spread the force.The nature of the bonding of a nano tube isdescribed by applied quantum chemistry, specifically, orbital hybridization.The chemical bonding of nano tubes are composed entirely of sp2 bonds,similar to those of graphite.The lightweight fiber, made up of millions of tinycarbon nano tubes, is starting to reveal exciting properties. The fiber is verystrong, lightweight and good at absorbing energy in the form of fragments

traveling at very high velocity. Inherent property of elasticity is the mainreason for it. Carbon nano tubes exhibit extraordinary mechanical propertiesIt is as stiff as diamond. The material is already up to several times stronger,tougher and stiffer than fibers currently used to make protective amour. Forbody armour, the strength of the fibers in a fabric is critical parameter.Recently preparing bullet proof t-shirts can save lots of people from bullethits. In future, these amours can be used for military applications.

8/3/2019 Cabon Nano

3/26

Technology that works at thenanometer scale of molecules and atoms will be a large part ofnano technology. This technology will be enabling greatimprovements in all the fields of human presence .Electronics is anarea where nano technology making great gain. CARBONNANOTUBES is one of the main applications of nano technology.

Carbon nano tubes are allotropes of carbon. They are of so manytypes. Among them single nano tubes have more significance. Acarbon nano tube is a one-atom thick sheet ofgraphite rolled upinto a seamless cylinderwith diameter on the order of a nanometer.This results in a nanostructure where the length-to-diameter ratio

exceeds 1,000,000. They exhibit extraordinary strength and uniqueelectrical properties. The inherent property of elasticity madethem to show rebounding property. The nano tubes are createdrapidly by squirting a carbon source, like ethanol, and an iron nanocatalyst through a hydrogen carrier, and into a furnace at 1,200

degrees Celsius.

8/3/2019 Cabon Nano

4/26

The size of the nano tube is in the order of few nano meters,approximately 1/50000th of the width of a human hair, while theycan be up to several millimeters in length. . Nano tubes are

mainly categorized as single-walled nano tubes and multi-wallednano tubes. Among them single walled tubes are used to makebullet proof vests which are mainly used for military applications.

8/3/2019 Cabon Nano

5/26

They had been discovered in 1991.The current huge interestin carbon nano tubes is a direct consequence of the synthesisof buckminsterfullerene, C60. The search was given newimportance when it was shown in 1990 that C60 could beproduced in a simple arc-evaporation apparatus readilyavailable in all laboratories. The tubes contained at least twolayers, often many more, and ranged in outer diameter fromabout 3 nm to 30 nm. They were invariably closed at bothends. In 1993, a new class of carbon nano tube was

discovered, with just a single layer. It was soon establishedthat these new fibers had a range of exceptional properties(see below), and this sparked off an explosion of researchinto carbon nano tubes Recent research has focused on

improving the quality of catalytically-produced nano tubes.

8/3/2019 Cabon Nano

6/26

8/3/2019 Cabon Nano

7/26

8/3/2019 Cabon Nano

8/26

The tubes can therefore be consideredas rolled-up graphene sheets. The first two of these, known asarmchair (top left) and zigzag (middle left) have a high degreeof symmetry. The terms "armchair" and "zigzag" refer to the

arrangement of hexagons around the circumference.The third class of tube, which in

practice is the most common, is known as chiral, meaning that itcan exist in two mirror-related forms. An example of a chiral nanotube is shown at the bottom left. Condensing on the walls of the

reaction vessel and some of it on the cathode. It is the deposit onthe cathode which contains the carbon nano tubes. Single-wallednano tubes are produced.

when Co and Ni or some other metal isadded to the anode. It has been known since the 195s, if not earlier,that carbon nano tubes can also be made by passing a carbon-containing gas, such as a hydrocarbon, over a catalyst. The catalystconsists of nano-sized particles of metal, usually Fe, Co or Ni.These particles catalyze the breakdown of the gaseous moleculesinto carbon, and a tube then begins to grow with a metal particleat the tip

8/3/2019 Cabon Nano

9/26

. It was shown in 1996 that single-walled nano tubes can alsobe produced catalytically. The perfection of carbon nanotubes produced in this way has generally been poorer thanthose made by arc-evaporation, but great improvements inthe technique have been made in recent years. The bigadvantage of catalytic synthesis over arc-evaporation is that itcan be scaled up for volume production. The third important

method for making carbon nano tubes involves using apowerful laser to vaporize a metal-graphite target. This canbe used to produce single-walled tubes with high yield.

8/3/2019 Cabon Nano

10/26

Types ofcarbon nano tubes

1.SINGLE WALLED : Single-walled nano tubes are generally

narrower than the multi walled tubes, with diameters typically in therange 1-2 nm, and tend to be curved rather than straight. The imageon the right shows some typical single-walled tubes Single-wallednano tubes are a very important variety of carbon nano tube becausethey exhibit important electric properties that are not shared by the

multi-walled carbon nano tube variants. These tubes are used tomake super strong amour bodies. They have elastic property andhence used to make bullet proof vests.

8/3/2019 Cabon Nano

11/26

2. MULTI WALLED :

Multi-walled nano tubes consist of

multiple layers of graphite rolled in on themselves to form atube shape. There are two models which can be used todescribe the structures of multi-walled nano tubes. Thespecial place of double-walled carbon nano tubes must beemphasized here because they combine very similarmorphology and properties as compared to SWNT, whileimproving significantly their resistance to chemicals. This isespecially important when fictionalization is required to addnew properties to the CNT.

8/3/2019 Cabon Nano

12/26

3. FULLERITE :

Fullerite are the solid-statemanifestation of fullerenes and related compounds and

materials. Being highly incompressible nano tube forms,polymerized single-walled nano tubes are a class of fulleritesand are comparable to diamond in terms of hardness.However, due to the way that nanotubes intertwine, they

don't have the corresponding crystal lattice that makes itpossible to cut diamonds neatly. This same structure results ina

8/3/2019 Cabon Nano

13/26

4. NANO BUD :

A stable nano bud structure

Carbon nano buds are a newly discovered material combiningtwo previously discovered allotropes of carbon: carbon nanotubes and fullerenes. In this new material fullerene-like "buds"are covalently bonded to the outer sidewalls of the underlyingcarbon nano tube. This hybrid material has useful properties of

both fullerenes and carbon nano tubes. In particular, they havebeen found to be exceptionally good field emitters.

mong all types, bullet proof vests can be made from singlewalled nano tubes.

8/3/2019 Cabon Nano

14/26

8/3/2019 Cabon Nano

15/26

One of the main applications ofcarbon nano tubes is super strong bullet proof vests. Bulletproof vests are woven by the carbon nano fibers which aremade up of millions of tiny carbon nano tubes is starting toreveal exciting properties. A new bullet proof material is

designed which actually rebounds the force of abullet. Bulletproof materials at the moment are designed tospread the force. The lightweight fiber, made up of millions oftiny carbon nano tubes, is starting to reveal exciting

properties the lightweight fiber. The fiber is very strong,lightweight and good at absorbing energy in the form offragments travelling at very high velocity. So it can be used asbody amour. Carbon nano tubes have great potential

applications in making ballistic-resistance materials.

8/3/2019 Cabon Nano

16/26

8/3/2019 Cabon Nano

17/26

8/3/2019 Cabon Nano

18/26

PRINCIPLE:The main principle is carbon nano fibers

are good at absorbing energy so they can absorb the energy coming fromthe bullet. The inherent property of elasticity makes the bullet torebound.

STRENGTH OFFIBRE:

It is 100% stronger than the steel.Lighter than aluminum

Conduct electricity as copper.

These fibers can be used as space elevators.

8/3/2019 Cabon Nano

19/26

Bulletproof jackets do not turn securityguards, police officers and armed forces into Robocops, repelling theforce of bullets in their stride. New research in carbon nanotechnologyhowever could give those in the line of fire materials which can bounce

bullets without a trace of damage.

8/3/2019 Cabon Nano

20/26

A research paper published in the Institute of Physics'Nanotechnology details how engineers from the Centre forAdvanced Materials Technology at the University of Sydney have

found a way to use the elasticity of carbon nano tubes to not onlystop bullets penetrating material but actually rebound their force.

8/3/2019 Cabon Nano

21/26

When the bullet strikes the jacket, the fibershows its elastic property and rebounds the bullet. The Engineersin Australia have designed a new bullet proof material which

actually rebounds the force of a bullet. Bulletproof materials atthe moment are designed to spread the force. The use ofnanotechnology in design means those in the line of fire can beshot without a flinch.

Also known as body amours, there aredifferent types of bullet proof vests. The most common is the softvest usually used by the police force and private security; it cannotstop ammunition of big caliber. Hard-plate reinforced vests arenecessary when heavy ammunition is involved; they are used as

part of the default equipment in the Army. Soft bullet proof vestsare formed from advanced woven fibers that can be sewn into vestsand other soft clothing. The fibers form a tight interlaced netwhich disperses the energy of the bullet reducing its speed until itstops.

8/3/2019 Cabon Nano

22/26

The most effective material used in body armor is Kevlar fiber.Kevlar is light as cloth, but five times stronger than a piece of steelof the same weight. When interlaced into a dense net, this

material can absorb a great amount of energy. The fivers areusually twisted individually and the material covered by a doublecoat of resin and plastic. The second most used material isVectran, which is two times stronger than Kevlar. New trends

include spider web, feathers and carbon nano tubes.

8/3/2019 Cabon Nano

23/26

The bullets do so much damagebecause of the focused blunt trauma: they focus all the impact in areduced area increasing the penetration rate. Bullet proof vests aredesigned to spread the energy laterally over the whole vest whiledeforming the bullet at the same time. The system works as the

net of a soccer goal, lateral tension of the net spreads the energy ofthe impact and stops the ball without reflecting it (in most cases)the collision is completely inelastic. When hard protective piecesare added, the bullets might be deflected instead of stopped, butin the case of soft body armor it is extremely difficult to deflect a

bullet, it will be trapped by the material and stopped.Most anti-ballistic materials, like

bullet-proof jackets and explosion-proof blankets, are currentlymade of multiple layers of Kevlar, Twaron or Dyneema fibers which stop bullets from penetrating by spreading the bullet's

force

8/3/2019 Cabon Nano

24/26

8/3/2019 Cabon Nano

25/26

We conclude that these bullet proofvests are very effective and essential for the coming generations.As these are made from carbon nano fibers, which are readilyavailable and less in cost, the coming generations will be

benefited more. These are safe and protective than the bulletproofs which are used in these days. A new generation of bullet-proof vests and anti-ballistic materials that are much moreeffective than those in use today.

8/3/2019 Cabon Nano

26/26

Although we might be making severalkilometers a day, it's a very thin fiber, weighing much less than a gram,"We have to scale this up to make kilograms. Before anyone will committhe huge investment needed to build a full-scale plant, they need to

know that it will make a good bullet-proof vest." The research is goingon to prepare protective body suits.

Body amour for women personal.Reinforced soft and hard body armour. Helmet and body protectivedevice. Breathable garment to be woven to improve the comfort of the

human body.