Alumina armor ceramics
Description: The monololithic plate of alumina ceramics is different from the bulletproof plate of small ceramic splicing. For example, the 250×300 insert board uses a whole piece of alumina ceramics as an energy-absorbing material to block bullet impact, so the advantage is that there is no gap in the ceramic surface, which is faster when it is combined with fiber materials, has a better overall protection effect and a nicer performance of resisting multiple bullets. Of K99 alumina, K95 alumina, and K95E alumina of the whole plate ceramic, the formula of alumina material is not the same, and each has its advantages and disadvantages.
I.sintering method
The technology method of densifying granular ceramic body and forming solid materials is called sintering. Sintering is a method to remove the void between the particles and 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. The most widely used sintering heating device is the electric furnace, which is usually called atmospheric pressure sintering or non-pressure sintering.
II. Physical properties
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, and is widely used in aerospace, automotive, energy, chemical and other fields. Because it has excellent mechanical properties, high hardness, strong wear resistance, good stability, small thermal expansion coefficient, good energy absorption, it is favored by military experts in various countries, and is widely used.
III.Bulletproof mechanism
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 alumina ceramics in the armor system is very attractive, and has become a widely used in body armor, vehicles, aircraft and other equipment protective armor.
IV.Product structure
The molecular formula of alumina ₃ 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, becoming the main component of alumina bulletproof ceramics.
Kingcera special porcelain production of alumina bulletproof armor ceramics, has alumina content of 99% and 95% two labels, Rockwell hardness up to HRA85-88. Through the military unit shooting test, the bullet impact resistance is strong, the depression value is low, the absorption capacity is strong, the effect is good.
V. Armor ceramic application test
Alumina bulletproof armor is used for the protection of military equipment such as tanks, armored vehicles, combat aircraft, and can also be applied to personal protective equipment, such as shrapnel protective clothing. It can also be used in the field of civil building safety, such as bank safes, security doors and building protection. It can effectively withstand the attack of high-speed shrapnel and artillery shells, and provide a safe and protective environment.
Kingcera 99/95 alumina bulletproof ceramic insert plate shooting test record
Ⅵ. Kingcera 99/95 alumina ceramic bulletprrof sheet index parameters
Parameter |
Unit |
99 Al₂O₃ |
K95 Al₂O₃ |
K95E Al₂O₃ |
Alumina content |
% |
≥99 |
≥95 |
<95 |
Bulk density |
g/cm³ |
≥3.8 |
≥3.8 |
≥3.75 |
Rockwell hardness |
HRA |
≥88 |
≥85 |
≥85 |
Vicker hardness |
Hv10 |
≥1500 |
≥1300 |
- |
Wear volumn |
cm³ |
≤0.02 |
- |
- |
Bending strength |
Mpa |
≥320 |
≥320 |
≥300 |
Compressive strength |
Mpa |
≥1300 |
≥1250 |
≥1250 |
Fracture toughness KIC |
(Mpa.m1/2) |
≥4.0 |
≥3.5 |
≥3.4 |
Thermal conductivity |
W/m.K |
20 |
20 |
20 |
Thermal expansion coefficient |
m/m.K |
7.2×10-6 |
7.2×10-6 |
7.2×10-6 |
With the continuous progress of science and technology, the performance of aluminum oxide bulletproof armor will be further improved. The preparation process of aluminum oxide bulletproof armor has been improved, and the production efficiency and quality stability of aluminum oxide armor are better, which can provide people with a higher level of security.
Ⅶ.Bulletproof insert plate special alumina ceramic bulletproof plate
Existing specifications, other specifications can be customized:
Single surface R400: 225 *250*5 ~ 20, 240*290*5 ~ 20
Multiple surfaces: 258*305**5 ~ 20