K99 alumina bulletproof ceramics

The technology method of densifying granular ceramic body and forming solid materials is called sintering, sintering is to remove the void between the particles, remove a small amount of gas and impurities and organic matter, so that the particles grow and combine with each other to form a new material method. The most widely used sintering heating device is the electric furnace, which is usually called atmospheric pressure sintering or non-pressure sintering.

The higher the purity of alumina ceramics, the higher the hardness. Secondly, it also has high wear resistance, high melting point, excellent insulation properties and various chemical stability, which is widely used in aerospace, automotive, energy, chemical and other fields. Because alumina ceramic has excellent mechanical properties, high hardness, strong wear resistance, good stability, small thermal expansion coefficient, it has good energy absorption. As a result, alumina ceramic is favored by military experts in various countries, and is widely used in different conditions. 

The reason why ceramics can be bulletproof is because of its high hardness, high strength and chemical inertness in many environments. It is superior to metal, which produces plastic deformation and absorbs energy when resisting the impact of the bullet, while ceramic produces little plastic deformation, and the bullet will be blunted or even broken due to its own high strength and hardness characteristics.

When the high-speed projectile body collides with the ceramic layer, the ceramic layer breaks or cracks and diffuses around the impact point to consume most of the energy of the projectile body, and then the high modulus fiber composite plate further consumes the remaining energy of the projectile body. Therefore, the application of 99 alumina ceramics in the armor system is very attractive, and is widely used in body armor, vehicles, aircraft and other equipment protective armor.

The molecular formula of alumina is Al₂O₃, and it has many homogeneous crystals. There are three main crystals, namely α-Al₂O₃, β-Al₂O₃, gamma-Al ₂O₃, which are different in structure and nature. Among them, the structure of α-Al₂O₃ is the most stable, also known as corundum. At high temperatures above 1300℃, Al₂O₃ is almost completely transformed into α-Al₂O₃, which has become the main component of alumina bulletproof ceramics.

The alumina arc ceramic bulletproof sheet produced by Kingcera, has alumina content up to 99%, Rockwell hardness up to HRA88. Through the military unit shooting test, the bullet impact resistance is strong, the depression value is low, the absorption capacity is strong. The overall effect is good.

As a level three and above body armor protective material, alumina can also be used as a protective device for armor protection.

Kingcera 99 alumina bulletproof ceramic insert plate shooting test record: