The structure of a bulletproof vest mainly consists of two parts: a jacket and a bulletproof layer.
Clothing covers are commonly made of synthetic fabrics to cover and protect the bulletproof layer, and some clothing covers also have a certain bulletproof effect.
The bulletproof layer is made of hard and soft materials such as metal, fiberglass, ceramics, nylon, and Kevlar (aramid), either single or composite, to allow the bullet and shrapnel to pop open and embed, and to dissipate the impact kinetic energy of the bullet and shrapnel, providing protection for the human body. The function of clothing covers has evolved from a single bulletproof layer in the past to high-performance bulletproof clothing covers with functions such as fire prevention, waterproofing, and camouflage today.
The thickness of the bulletproof layer is determined based on the optimal balance between protective performance and wearing comfort for different users. The structure of the bulletproof layer can be single or composite. There are various composite materials for bulletproof materials, as well as composite materials for bulletproof and shock-absorbing. Some bulletproof materials are made as a whole, while others are made into pieces and overlapped one by one. The overall activity is inconvenient. Currently, rigid materials are generally made into sheets, which have greater mobility when worn, while soft bulletproof materials are generally made as a whole.
The development of bulletproof materials has gone through a long historical process. From ordinary steel to alloy steel, from metal materials to fiberglass, from ordinary chemical fibers to aramid (Kevlar), from single materials to composite materials. Every step taken greatly improves the performance of the bulletproof vest. Although bulletproof materials are diverse and diverse, they can be summarized into only six categories: metal (including alloy materials), fiberglass, ceramics, nylon, silicon carbide, and Kevlar (a type of aramid fiber material product). Among them, the latter three are soft bulletproof materials with many excellent properties, which have gradually replaced the first three rigid materials. Nylon is a soft bulletproof material that uses multiple layers of high-strength nylon cloth, which can effectively defend against pistol bullets and submachine gun bullets, and is relatively lightweight; Silicon carbide fiber is an inorganic fiber with a particularly high elastic modulus. When subjected to impact, it tears and absorbs the energy of shrapnel, weakening the harm of shrapnel to the human body; Kevlar fiber (a type of aramid fiber material product) has high temperature resistance, high strength, and high modulus, and its strength is 5 times that of steel. The bulletproof vest made of this material has a good bulletproof effect and is comfortable to wear. When a bullet or fragment hits the Kevlar layer, its high strength blocks the bullet, causing the fiber itself to deform and consume the kinetic energy of the bullet or fragment, thereby protecting the safety of the wearer.
Recently, ultra-high molecular weight polyethylene has been used for bulletproof layers. Nylon, Kevlar, and ultra-high molecular weight polyethylene are all made of their soft fabrics or fabrics impregnated with resin like chemicals to create bulletproof layers. Their bulletproof mechanism is the same: they use their strength to resist bullets or fragments. When they cannot resist, the fibers twist and deform, embedding bullets or fragments. The first layer cannot stop them, and there is also a second layer, which has a bit of a sense of continuity. The main factors that determine its bulletproof performance are the weight and thickness of the fabric, as well as its structure; Next is the organizational structure for making bulletproof vest materials. Experiments have shown that a plain weave dense structure fabric of 200 grams per square meter has the best bulletproof effect. Sewing three layers of such fabric together in rows is enough to defend against rifle bullets. The bulletproof vests worn by the US ground forces are made of 13 layers of Kevlar fabric at a weight of 475 grams per square meter, with an olive green cover. The outer layer of the garment cover is made of 272 grams/m2 bulletproof nylon fabric, which has undergone water blocking treatment and is a four color jungle green color; The inner layer is the same as the outer layer, using olive green. The bulletproof layer of the bulletproof vest and the inner and outer layers of the jacket have a bulletproof effect. Clothing covers are commonly made of synthetic fabrics to cover and protect the bulletproof layer, and some clothing covers also have a certain bulletproof effect. The bulletproof layer is made of hard and soft materials such as metal, fiberglass, ceramics, nylon, and Kevlar (aramid), either single or composite, to allow the bullet and shrapnel to pop open and embed, and to dissipate the impact kinetic energy of the bullet and shrapnel, providing protection for the human body. The function of clothing covers has evolved from a single bulletproof layer in the past to high-performance bulletproof clothing covers with functions such as fire prevention, waterproofing, and camouflage today. The thickness of the bulletproof layer is determined based on the optimal balance between protective performance and wearing comfort for different users. The structure of the bulletproof layer can be single or composite. There are various composite materials for bulletproof materials, as well as composite materials for bulletproof and shock-absorbing. Some bulletproof materials are made as a whole, while others are made into pieces and overlapped one by one. The overall activity is inconvenient. Currently, rigid materials are generally made into sheets, which have greater mobility when worn, while soft bulletproof materials are generally made as a whole.