Performance Parameters of Alumina Ceramics

Aluminum oxide ceramics (Al₂O₃) are one of the most important advanced ceramic materials, known for their excellent mechanical strength, outstanding electrical insulation performance, and outstanding chemical corrosion resistance. This material is widely used in fields such as electronics, machinery, chemical engineering, and healthcare.

About Alumina Ceramic

Aluminum oxide ceramics are composed of high-purity aluminum oxide (Al₂O₃) with a dense crystal structure, endowing it with high hardness, high wear resistance, and good thermal stability. 

According to the alumina content, it can be divided into:

99% alumina ceramics: used for high-temperature crucibles, precision ceramic bearings, and electronic substrates

95% -96% alumina ceramics: suitable for wear-resistant parts, circuit substrates, and mechanical seals

85% -90% alumina ceramics: mainly used for general industrial wear-resistant components

Characteristics of alumina ceramics

physical property

Color: White (the higher the purity, the whiter)

Density: 3.7-3.9 g/cm³ (99% purity)

Thermal expansion coefficient (25-1000 ° C): 8-9 × 10⁻⁶/K

Mechanical properties

Bending strength: 300-400 MPa

Hardness: 9 Mohs (second only to diamond)

Elastic modulus: 300-400 GPa

Thermal Properties 

Maximum operating temperature: 1600°C (short-term up to 1800°C)

Thermal conductivity: 20-30 W/(m · K) (high thermal conductivity)

Electrical Property

Volume resistivity (20°C):>10¹⁴Ω·cm

Dielectric strength: 15-20 kV/mm

Advantages of alumina ceramics

✔  Ultra high hardness - second only to diamond and silicon carbide

✔  Excellent wear resistance - more than 10 times that of steel

✔  Good electrical insulation - excellent high-frequency insulation performance

✔  High temperature resistance - can be used for a long time at 1600°C

✔  Chemical stability - acid and alkali corrosion resistance (excluding HF)

✔  Biocompatibility - Can be used for medical implants

Typical applications of alumina ceramics

Electronics industry: integrated circuit substrates, vacuum tube casings, high-voltage insulation components

Mechanical industry: ceramic bearings, mechanical seals, wear-resistant lining plates

Chemical equipment: corrosion-resistant pump valves, reactor liner

Medical field: artificial joints, dental implants

High temperature applications: thermocouple protection tube, high-temperature furnace lining

conclusion

Alumina ceramics are the most cost-effective engineering ceramic materials, with irreplaceable advantages in applications that require high hardness, high wear resistance, and good insulation. For applications that require extreme wear resistance (such as mechanical seals) or high-frequency insulation (such as electronic substrates), alumina ceramics are the best choice.

Customized service

We can provide various specifications of alumina ceramic parts processing, including precision grinding, drilling, and complex shape processing. Please feel free to provide drawings for inquiry!