In the 1950s, the US military took the lead in using nylon, a soft synthetic fiber material, to make bulletproof vests. This is the prototype of the modern bulletproof vest. What is the internal structure of a bulletproof vest? Could it be made of many steel plates? You are really wrong. In modern bulletproof vests, there are no steel plates, all of which are made of fibers.
A foreign netizen bought a conventional bulletproof vest on the Internet. To his surprise, he found that the whole bulletproof vest was not the same as his imagination. In his mind, the bulletproof vest was hard, but the texture of the bulletproof vest he bought was very soft, and there was no hard feeling at all. In order to study the internal structure of bulletproof vests, the foreign little brother cut the bulletproof vests with a professional cutting tool, because no matter how hard he tried, he couldn’t tear them open with his bare hands. After cutting, the foreign little brother was simply stunned.
He was surprised to find that there was no steel plate inside the bulletproof vest, even no protective material similar to steel plate. There was only a kind of fiber-like material woven, which felt soft, but no matter how hard it was pulled, this fiber material could not be disconnected. Although it was soft, it was very strong.
In fact, modern body armor was originally made of nylon fiber. Although this kind of behavior has a good protective effect, it weighs more than 4.5kg, and it is very stuffy to wear, which will reduce the combat capability of soldiers by more than 30%. Until the 1970s, Kevlar, a synthetic fiber, began to become the material for producing bulletproof vests. Kevlar’s full name is poly (p-phenylene terephthalamide) fiber, and its tensile strength is extremely high, which is more than twice that of nylon fiber. Since Kevlar has become the main material of body armor, the performance of body armor has been significantly improved. Experiments show that the kinetic energy absorption capacity of Kelaf is 1.6 times that of nylon and 2 times that of steel, and multilayer Kelaf fabric, though not as hard as steel, still has a good protective effect on bullets.
The bulletproof vest made of Kevlar has the characteristics of high strength, good toughness, high density, lightweight, etc., and it is also resistant to high temperature and chemical corrosion, with excellent insulation and flexibility. Compared with bulletproof vests made of other materials, the bulletproof vests made of Kevlar are very comfortable to wear, and the soldiers who wear them say they are very close to each other. So it is favored by many countries’ armies and police.