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Kevlar Fibers Whats the Kevlar ?Kevlar ( Trade name ) is a material formed by combining para-phenylenediamine and terephthaloyl chloride.

Whats the Kevlar ?Aromatic polyamide (aramid) threads are the result.

Production Kevlar issynthesizedin solution from the monomers 1:4 phenylene-diamine( para-phenylenediamine ) andterephthaloyl chloridein a condensation reactionyieldinghydrochloric acidas a byproduct. The result hasliquid-crystallinebehavior, and mechanic drawing orients the polymer chains in the fiber's direction.

Productionliquid-crystalline material extruded through a spinneret (a small metal plate full of tiny holes that looks like a shower head) to form Kevlar yarn. The Kevlar fiber then passes through a cooling bath to help it harden. After being sprayed with water, the synthetic fiber is wound onto rolls. If layers of the woven Kevlar are combined with layers of resin, the resulting rigid material is light and has twenty times the strength of steel. ProductionSpinningis a major part of thetextile industry. It is part of the textile manufacturing process wherefiberare converted intoyarn, thenfabrics.

General Features of KEVLAR High Tensile Strength at Low WeightLow Elongation to Break High Modulus (Structural Rigidity)Low Electrical ConductivityHigh Chemical ResistanceLow Thermal ShrinkageHigh Toughness (Work-To-Break)Excellent Dimensional StabilityHigh Cut ResistanceFlame Resistant, Self-Extinguishing

Mechanical Properties of Kevlar

Some of Kevlar type & ApplicationsThere are three main types of Kevlar.1. Kevlaris used as a reinforcement material for some car tyres and bicycle tyres. It helps dramatically reduce puncture rates.

This standard of tyre is more expensive than ordinary road tyres. They are of particular use with 4 x 4 vehicles, especially when the vehicle is being used off road and far away from recovery services.

2. Kevlar 29is used in the manufacture of body armour (panels) for lightweight military vehicles. A good example is the US Armys Bradley Fighting Vehicle. This has been used extensively in Iraq and Afghanistan. Kevlar 29 was selected for its armour, because it is lightweight and withstands attack from RPGs. The Kevlar 29 panels protect the soldiers inside the vehicle.Kevlar 29 is ideal because it is lightweight and non-flammable and it offers protection from high temperatures (fire bombs, etc...). Kevlar 29 can also withstand the harsh environmental conditions, found in hot climates.

113. Kevlar 49is used for specialist boat hulls and in the aerospace industry. It is popular as a material for boats because it is lightweight and can withstand a considerable amount of force(torque - twisting force), tensile stress and impact. Hulls manufactured from traditional materials, such as fibreglass, are limited in their resistance to forces and stress. Also , a lightweight boat is faster on the water and uses less fuel to complete distances.

3. Kevlar 49 .Eurofighter is relatively light compared to other similar fighter jets, due to the selection of Kevlar 49 as a material in its manufacture. This means that it can fly faster and further, before in-flight refuelling is needed. It is more agile than its rivals due to excellent force (torque - twisting force) and tensile stress resistance. The plane is more likely to survive being hit by small arms fire, compared to other fighter planes, as Kevlar 49 has excellent impact resistance.

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