Aramid fibers are man-made high-performance fibers, with molecules that are characterized by relatively rigid polymer chains. These molecules are linked by strong hydrogen bonds that transfer mechanical stress very efficiently, making it possible to use chains of relatively low molecular weight.
Aramid fibers are a class of heat-resistant and strong synthetic fibers. They are used in aerospace and military applications, for ballistic-rated body armor fabric and ballistic composites, in marine cordage, marine hull reinforcement, and as an asbestos substitute.
Aramid fiber was the first organic fiber used as reinforcement in advanced composites with high enough tensile modulus and strength. They have much better mechanical properties than steel and glass fibers on an equal weight basis. Aramid fibers are inherently heat- and flame-resistant, which maintain these properties at high temperatures.
The term aramid is short for aromatic polyamide. Aromatic polyamides were first applied commercially as meta-aramid fibers in the early 1960s, with para-aramid fibers being developed in the 1960s and 1970s.
Aramid fibers share some general characteristics that distinguish them from other synthetic fibers:
- High strength
- Good resistance to abrasion
- Good resistance to organic solvents
- Non-conductive
- No melting point
- Low flammability
- Good fabric integrity at elevated temperatures
These unique characteristics derive from the combination of having stiff polymer molecules with a strong crystal orientation as well as close interaction between the polymer chains due to the hydrogen bonds.
Aramid (Kevlar) fiber fabrics Performance and characteristics With ultra-high strength, high modulus and high temperature resistance, acid and alkali resistance, light and other good performance, its strength is 5-6 times of steel wire, the modulus is 2-3 times of the steel wire or glass fiber, its toughness is 2 times of the steel wire while it only weighs about 1/5 of steel wire. In around a temperature of 560 °C, it does not decompose and melt. It has a good insulation and anti-aging properties with a long life cycle.
Main application Tires, bullet-proof vest, aircraft,spacecraft, sporting goods, conveyor belts, high strength ropes, constructions and cars ect.
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