Introduction to alumina ceramic materials
Alumina, as a material for precision ceramics, possesses several excellent properties, including high hardness, excellent chemical stability, high-temperature stability, good insulation properties, and dimensional stability. This makes it widely applicable in various fields such as wear-resistant parts, chemical vessels, high-temperature heating elements, electronic insulators, and components requiring high precision dimensional control.
Features
Alumina (Al2O3) is a very common and widely used ceramic material. It is renowned for its excellent overall performance and high reliability, and is used in many demanding industrial fields.
1. Wide range of applications and balanced mechanical properties
Alumina ceramics are widely popular due to their balanced mechanical properties, including high strength, high hardness, and good wear resistance. These characteristics enable alumina to play a crucial role in many fields.
High-Temperature Industrial Applications: Alumina is very common in the manufacture of refractory materials for high-temperature industrial furnaces. Its high melting point and stability allow it to operate in extreme high-temperature environments without deformation or damage.
Electronic Components: Alumina is also widely used in the electronics industry, particularly in the manufacture of substrates, insulators, and packaging materials. Its excellent electrical insulation and thermal conductivity make it an ideal material for electronic components.
2. Stability of chemical and physical properties
The stability of the chemical and physical properties of alumina ceramics makes them an indispensable material in precision industries. These properties include heat resistance, high thermal conductivity, high strength and hardness, as well as excellent electrical insulation and corrosion resistance.
Thermal Properties: Alumina’s heat resistance and good thermal conductivity make it highly useful in applications requiring rapid heat dissipation, such as LED lighting and power electronics.
Mechanical Properties: High strength and hardness ensure the durability of alumina under physical stress, which is particularly important in aerospace and automotive manufacturing.
Other Properties: Alumina’s high electrical insulation and strong corrosion resistance make it suitable for chemical processing environments and electrical applications. Furthermore, its high biocompatibility makes it highly sought after in medical devices and bio-implant materials.
| Primary characteristics | ||||||
| Type | Unit | Alumina | ||||
| Malzeme | \ | 95% | 96% | 99% | 99.50% | 99.70% |
| Al2O3 | Al2O3 | Al2O3 | Al2O3 | Al2O3 | ||
| Colour | \ | White | White | Ivory White | Ivory White | Ivory White |
| Density | g/cm3 | 3.7 | 3.7 | 3.85 | 3.9 | 3.9 |
| Mechanical properties | ||||||
| Type | Unit | Alumina | ||||
| Malzeme | \ | 95% | 96% | 99% | 99.50% | 99.70% |
| Al2O3 | Al2O3 | Al2O3 | Al2O3 | Al2O3 | ||
| Colour | \ | White | White | Ivory White | Ivory White | Ivory White |
| Flexural Strength(20℃) | Mpa | 300 | 300 | 330 | 360 | 380 |
| Compressive Strength(20℃) | Mpa | 2000 | 2000 | 2000 | 2350 | |
| Modulus of Elastic(young)(20℃) | Gpa | 270 | 275 | 370 | 370 | 380 |
| Tracture Toughness(20℃) | MPam½ | 3.5 | 3.5 | 4 | 4 | |
| Poi sion’s Ratio(20℃) | \ | 0.2 | 0.22 | 0.22 | ||
| Hardness HRA(20℃) | HRA | 90 | 90 | 90 | ||
| Vickers Hardness(HV1) | kg/mm2 | 1600 | 1600 | 1600 | 1650 | 1750 |
| Rockwell Hardness(45N) | R45N | 83.5 | 83.5 | 83.5 | ||
| Thermal properties | ||||||
| Type | Unit | Alumina | ||||
| Malzeme | \ | 95% | 96% | 99% | 99.50% | 99.70% |
| Al2O3 | Al2O3 | Al2O3 | Al2O3 | Al2O3 | ||
| Colour | \ | White | White | Ivory White | Ivory White | Ivory White |
| Thermal Expansion Coefficient | 10-6K-1 | 6.5 | 6.5 | 7.6 | 7.2 | 7.2 |
| Thermal Conductivity | W/mk | 20 | 25 | 27.5 | 32 | 32 |
| Thermal Shock Resistance | △T.℃ | 200 | 200 | 200 | 250 | |
| Specific Heat Capacity | J/g·k | 0.79 | 0.78 | 0.79 | ||
| Max working Temperature(In Oxidizing) | ℃ | 1600 | 1600 | 1650 | 1650 | |
| Electrical properties | ||||||
| Type | Unit | Alumina | ||||
| Malzeme | \ | 95% | 96% | 99% | 99.50% | 99.70% |
| Al2O3 | Al2O3 | Al2O3 | Al2O3 | Al2O3 | ||
| Colour | \ | White | White | Ivory White | Ivory White | Ivory White |
| Vol une Resistivity at 20℃ | Ωcm | 1014 | 1014 | 1014 | 1014 | 1014 |
| Dielectric Strength | KV/mm | 10 | 10 | 10 | 15 | 15 |
| Dielectric Constant | \ | 9 | 9 | 9.1 | 9.9 | 9.9 |
| Dielectric LossAngle at 20℃,1MHz20℃ | tanδ | 3*10-4 | 2*10-4 | 3*10-4 | 1*10-4 | 1*10-4 |