The Magic of Bulletproof Panels
In today's special international environment, bulletproof boards (also called bulletproof boards, bulletproof sheets) are highly valued by people, but there are various bulletproof boards on the market, and their performances vary greatly. Common bulletproof panels are divided into three categories, namely steel bulletproof panels, polyethylene PE bulletproof panels and ceramic bulletproof panels. Before the introduction, let's take a look at the protection level of bulletproof products
There are different classification standards for protection levels, and the NIJ bulletproof standard formulated by the National Institute of Justice of the United States is currently a relatively common international standard. Many bulletproof product manufacturers and criminal justice agencies use the test methods specified in this standard to determine Protection standard for bulletproof products. NIJ standards will also be regularly updated and improved. Currently, the latest version of NIJ is 0101.06, which is a revised version of NIJ 0101.04 issued in September 2000.
The following is a simple and intuitive introduction to the various bulletproof levels under the NIJ 0101.06 standard.
According to the NIJ 0101.06 standard, we divide bulletproof products into five grades: IIA, II, IIIA, III, and IV. Among them, grades IIA, II and IIIA are for pistol bullets; grades III and IV are for rifle bullets.
Level IIA: It needs to be able to defend against 9mm round-nosed full-metal armored projectile (FMJ), the minimum impact velocity does not exceed 332m/s (projectile weight 8 grams), and 40 S & W caliber full-metal armored projectile (FMJ), the minimum impact velocity is not more than 332m/s More than 312m/s (11.7g bullet weight). Level IIA is the lowest level in the defense level. It can defend against the attack of less powerful bullets such as 9mm FMJ. It is mainly aimed at application scenarios with relatively small risks. come less and less.Level II: It needs to be able to defend against 9mm round-nosed full metal armor (FMJ) and .357 Magnum armored darts, with a minimum impact velocity of no more than 427m/s (projectile weight 10.2 grams).
Defense Level Against Pistols
The NIJ's defense ratings for pistols are IIA, II, and IIIA.
Compared with the IIA level, the protection level of the II level is better, and it can defend against the threat of the .357 Magnum armored dart bullet. Also due to the limitation of the defense level, the level II defense products are becoming less and less, but there are currently some stealth ultra-thin bulletproof Clothes will choose to use this level.
Level IIIA: It needs to be able to defend against 9mm round-nosed full metal armor (FMJ), the minimum impact velocity does not exceed 427m/s (bullet weight 8.0g), and .44 Magnum semi-armored hollow point projectile, the minimum impact velocity does not exceed 427m /s, (the bomb weighs 15.6 grams). Level IIIA can deal with the threat of higher level pistols, and can meet the protection needs of most daily situations. This level is the most widely used level of body armor at present, and the protection level of body armor currently required is basically level IIIA.
Defense Level Against Rifles
The NIJ's defense classes against rifles are divided into classes III and IV. To defend this level, you need to use hard bulletproof inserts.
Level III: It needs to be able to defend against M80 full metal jacket (FMJ), and the minimum bullet speed does not exceed 838m/s (the bullet weighs 9.6 grams). It can deal with the conventional bullets of M80, M193, AK and other rifles. This is also the most used defense level for bulletproof inserts. There are many products of different materials that can be selected under this level.
Level IV: It needs to be able to defend against .30 caliber armor-piercing projectiles (M2 AP used by the US military), and the minimum speed does not exceed 869m/s, (the projectile weighs 10.8 grams). Level IV can also protect against AP or API rounds of other rifles such as AK, M80, SS109, M193. Class IV bulletproof products have a high defense index and can defend against most rifle bullets. It is mainly aimed at application scenarios with higher risk levels. For example, in some military activities with relatively high environmental risks, it is required to use products with such protection capabilities.On the basis of understanding the basic knowledge of the bulletproof level, let's compare the performance of the three bulletproof plates.
Make the best choice according to the bulletproof performance of the bulletproof plate:
Steel bulletproof panels have been in use since World War II and dominated the mainstream market for bulletproof panels decades ago. However, after the development of polyethylene bulletproof panels and ceramic bulletproof panels, steel bulletproof panels were gradually replaced. Although it is still used today, the number is small.
Steel bulletproof plate
Compared with the new type of bulletproof plate, the steel bulletproof plate is prone to fragmentation after being shot by a bullet, which will cause secondary crushing damage to the human body. Moreover, compared with the other two materials, the steel bulletproof plate under the same protection level is heavier, which consumes more physical strength of the wearer and reduces flexibility. Although the steel bulletproof board is the cheapest of the three boards, overall, it is not recommended as the first choice.
Polyethylene PE bulletproof board
Ethylene PE is a new type of thermoplastic material. Polyethylene PE bulletproof boards are manufactured by bonding unidirectional ultra-high molecular weight polyethylene fibers on high-density polyethylene boards. The sheet is cut into shape, placed in a mold, and compressed under high temperature and pressure to obtain a cohesive rigid armor plate. Polyethylene "sticks" to the bullet by using the friction caused by the bullet's rotation to melt the polyethylene. After the rotation stops, the heat is no longer generated and the polyethylene cools down and hardens again.
The quality of polyethylene PE boards is generally about 1 to 1.5kg, which is much lighter than steel boards and ceramic bulletproof boards. However, due to the limitations of the current material technology, the highest protection level that pure PE inserts can achieve is NIJ III, which cannot defend against rifle armor-piercing bullets and more powerful bullets. Moreover, the cost of polyethylene PE is high, and its price is often higher than that of ceramic inserts. 200% to 300% more expensive is not a good choice either.
Ceramic bulletproof plate
Ceramic inserts can use a variety of materials, the more common ones are alumina, silicon carbide and boron carbide. Ceramics are bulletproof because of their high specific stiffness, high specific strength, and chemical inertness in many environments. It is better than metal in that metal materials will produce plastic deformation and absorb energy when resisting the impact of bullets, while ceramics will hardly produce plastic deformation, and bullets will be passivated or even broken due to their own high strength and hardness characteristics. The bulletproof layer adopts bulletproof ceramics and high-strength and high-modulus fiber composite board. When the high-speed projectile collides with the ceramic layer, the ceramic layer breaks or cracks and spreads around the center of the impact point to consume most of the energy of the projectile. The modulus fiber composite board further consumes the remaining energy of the projectile. Therefore, the application of advanced ceramics in armor systems is very attractive and has become widely used in protective armor for body armor, vehicles, aircraft, etc.
Under the same size and protection level, the ceramic board is lighter than the steel board, and the price is lower than that of the PE board, and even the thickness can be thinner.
Generally speaking, the steel bulletproof plate is simple and low in price, but its weight is too large, and it is easy to cause secondary damage to the user; while the polyethylene PE bulletproof plate is light in weight, but its bulletproof ability is poor, and it can only reach the third level of the American standard. And the price is expensive; comparatively speaking, the ceramic bulletproof plate is not only light in weight and low in price, but also has excellent bulletproof ability. Jingcheng’s alumina ceramic bulletproof plate has passed the target shooting test, and the bulletproof grade can reach American standard level 4 and national standard level 6 , the performance of silicon carbide ceramic bulletproof plate is higher than that of alumina plate, which is the best choice for bulletproof plate.