Alumina ceramic（Al2O3)< span style="color: rgb(102, 102, 102); letter-spacing: 0pt; font-size: 10.5pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">It is a very wear-resistant precision ceramic material and is widely used in all walks of life. The main forming methods of alumina ceramic products are ：Dry pressing, isostatic pressing, injection molding and tape casting, different product shapes, sizes and complex shapes Alumina ceramic products sintered at high temperatures require different molding methods than precision products, which can only be processed using a diamond grinding process.work. The purity of common alumina ceramics is 90%-99.9%.
|
Performance parameters of alumina ceramics |
|
Material |
Alumina Al2O3 |
|
Performance |
Unit |
99.99% |
99.70% |
99.50% |
99% |
97% |
95% |
|
Density |
g/cm³ |
3.95 |
3.94 |
3.9 |
3.8 |
3.75 |
3.7 |
|
Straightness |
‰ |
1 |
1 |
1 |
1 |
1 |
1 |
|
Hardness |
Mohs Scale |
9 |
9 |
9 |
9 |
8.9 |
8.8 |
|
Water absorption |
% |
≤0.2 |
≤0.2 |
≤0.2 |
≤0.2 |
≤0.2 |
≤0.2 |
|
Flexural strength |
MPa |
375 |
375 |
370 |
340 |
320 |
304 |
|
Compressive strength |
Mpa |
2300 |
2300 |
2300 |
2210 |
2100 |
1910 |
|
Maximum operating temperature |
℃ |
1750 |
1750 |
1750 |
1700 |
1650 |
1500 |
|
℃ to 800℃) Thermal expansion coefficient |
10-6/℃ |
8 |
7.8 |
7.8 |
7.7 |
7.6 |
7.5 |
|
Fracture toughness |
MPa *m1/2 |
4.4 |
4.3 |
4.3 |
4.2 |
4 |
3.8 |
|
Dielectric strength |
AC-kv/mm |
9 |
8.7 |
8.7 |
8.7 |
8.5 |
8.3 |
|
Dielectric loss |
—— |
< 0.0001 |
< 0.0001 |
< 0.0001 |
0.0001 |
0.0002 |
0.0002 |
|
Dielectric constant |
25º C@1MHz |
9.8 |
9.7 |
9.7 |
9.5 |
9.3 |
9.2 |
|
Resistivity |
Ω*mm2 /m |
>1014 |
>1014 |
>1014 |
>1014 |
>1014 |
>1014 |
|
Thermal conductivity |
W/m·K |
30 |
30 |
30 |
29 |
27.5 |
25 |
Advantages of alumina ceramics：
1. Alumina ceramics have excellent insulation, small high-frequency loss but good high-frequency insulation;
2, alumina ceramics are heat resistant, have small thermal expansion coefficient, high mechanical strength and good thermal conductivity.
3, alumina ceramics have the characteristics of chemical corrosion resistance and molten metal resistance.
4 Alumina ceramics are non-combustible, stainless, strong and not easily damaged. They have excellent properties that are incomparable to other organic materials and metal materials.
5, alumina ceramic wear resistance, but the hardness is the same as corundum,canAchieving Mohs hardness level nine, the wear resistance is comparable to that of supercarbide.
Performance of alumina ceramics< /span>：
1, Hardness Big
After determination,AluminaThe Rockwell hardness is HRA80-90. The hardness is only second to diamond, and far exceeds the wear resistance of wear-resistant steel and stainless steel.
2, excellent wear resistance
Alumina ceramic material has been measured by the Powder Metallurgy Research Institute of Central South University of Technology and its wear resistance is 266 times that of manganese steel. 171.5 times that of high chromium cast iron. According to our customer tracking surveys over more than ten years, it can extend the service life of equipment by at least ten times under the same working conditions.
3, light weight
The density of alumina ceramic material is3.7~3.95g/cm³, only half of steel, It can also greatly reduce the equipment load.
4、Wide scope of application
Alumina ceramics are widely used in machinery, optical fiber, cutting tools, medical care, food, chemical industry, aerospace and other industries.
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Common products include: sealing accessories , valve seats, mechanical components, high-temperature electrical insulators, high-voltage insulators, electronic components and substrates, bulletproof armor, bearings, wear-resistant or corrosion-resistant linings, semiconductor parts, laser chambers, trays, sandblasting nozzles, knife sharpeners, microwaves Components, frictionless clutches, high temperature kiln furniture, etc.
