Alumina Ceramics (Al₂O₃) : High-Performance Solutions for Demanding Applications

Yes, alumina is a type of ceramic.

Alumina ceramic is a kind of advanced ceramic material. It is made from alumina (Al₂O₃) as the main raw material. Alumina ceramics have many excellent properties, such as high hardness, high melting point, good chemical stability, high electrical resistivity, and low dielectric loss. They are widely used in various fields, including electronics, machinery, aerospace, and medical devices.

Yes. Alumina ceramic is extremely durable due to its high hardness (Mohs ≥ 9), excellent wear resistance, and chemical inertness. It performs reliably in harsh environments, including high temperatures and corrosive conditions.

• High hardness (≥ 9 Mohs)
• High dielectric strength (10–12 kV/mm)
• Low thermal expansion (6–8 × 10⁻⁶/K)
• High thermal conductivity (18–30 W/m·K)
• Excellent corrosion and wear resistance
• High volume resistivity (>10¹² Ω·cm)

We offer alumina ceramics in various purities, including 95%, 99%, 99.5%, 99.7%, and 99.8%. Higher purity grades provide better electrical insulation, thermal conductivity, and mechanical strength.

Several shaping methods can be employed in the fabrication of alumina ceramics, which are typically derived from bauxite. These methods include injection molding,isostatic pressing, die pressing,  slip casting, diamond machining, and extrusion.

Cutting aluminum oxide ceramic involves several methods, each suited to different applications:

1. Diamond sawing: Common, cost-effective, used for general shaping and cutting (tiles, substrates, wear-resistant parts).
2. Laser cutting: High precision, intricate designs (microfluidic devices, thin sheets, medical devices).
3. Water jet cutting: Thick pieces, complex shapes, minimal heat (armor plating, cutting tools).
4. Ultrasonic machining: Intricate shapes, small parts (microelectronics, microfluidics).
5. Line sawing: Large blocks, complex 3D shapes (semiconductor industry, large components).

Cleaning aluminum oxide ceramic is generally straightforward due to its chemical resistance. The best method depends on the type of soiling:

1. General Cleaning: For dust and light dirt, warm soapy water and a soft cloth or sponge are usually sufficient. Rinse thoroughly and dry completely.
2. Stubborn Stains: For more stubborn stains, a mild abrasive cleaner can be used. Baking soda or a non-abrasive commercial cleaner designed for ceramics are good options. Apply with a soft cloth or sponge and rub gently. Avoid harsh scouring pads or steel wool, as these can scratch the surface.
3. Grease or Oil: A degreaser or solvent can be used to remove grease or oil. Isopropyl alcohol is a good option. Apply with a soft cloth and rinse thoroughly.
4. Baked-on Deposits: For baked-on deposits, soaking the ceramic in hot soapy water for an extended period can help loosen the debris. A plastic scraper can then be used to carefully remove the softened deposits.
5. Ultrasonic Cleaning: For intricate parts or difficult-to-reach areas, ultrasonic cleaning can be effective. This method uses high-frequency sound waves in a cleaning solution to remove contaminants.

Important Considerations:

1. Avoid using harsh chemicals like strong acids or alkalis, as these can potentially damage the ceramic over time, especially at elevated temperatures or concentrations.
2. Be cautious with metal tools, as they can scratch the surface. Plastic or wooden tools are preferred.
3. Always test any cleaning method on a small, inconspicuous area first to ensure it doesn't damage the ceramic.

Zirconia:Exceptional toughness, high strength, good wear resistance, excellent biocompatibility.But lower thermal conductivity, higher cost.

Alumina:High hardness, good wear resistance, good chemical resistance, lower cost.But lower toughness compared to zirconia, moderate thermal conductivity.

If you are not sure which material to choose for your product, please contact us to recommend for you.

Working with alumina (Al2O3) means shaping an advanced ceramic that's known for being extremely hard but also brittle. Its great properties – like hardness, wear resistance, high-temperature stability, electrical insulation, and chemical resistance – make it crucial for many demanding industrial applications. However, that same hardness and brittleness make it tough to machine using regular methods.

The Main Challenges

• • • It's Very Hard: Alumina ranks 9 on the Mohs scale, so it chews up standard cutting tools quickly. Diamond tooling is usually required.
    • It's Brittle: The material tends to chip or crack under the stress of machining. This requires careful control over the process and using the right techniques to avoid damage.
    • Poor Heat Transfer: Heat builds up right where the cutting happens because alumina doesn't conduct it away well. This can lead to thermal damage or warping, making good cooling very important.

Common Machining Methods

Because of these challenges, specialized techniques are needed:

• • • Diamond Grinding: This is the go-to method. It uses diamond abrasive tools to grind the alumina, allowing for high precision and smooth finishes.
    • Laser Machining: A non-contact method using a focused laser beam to cut, drill, or shape the material. It's great for intricate details and complex designs.
    • Ultrasonic Machining (USM): Uses a tool vibrating at very high frequency combined with a slurry containing abrasive grit. The vibration hammers the grit against the alumina, slowly eroding it – useful for complex shapes.
    • Abrasive Waterjet: Shoots a high-pressure stream of water mixed with abrasive particles to cut through the material. It's often used for thicker sections but typically isn't as precise as grinding.
    • Electrical Discharge Machining (EDM): Generally only an option for specific types of alumina that are electrically conductive, or if special techniques are employed.

Absolutely. We provide precision machining services for alumina ceramics, including CNC grinding, cutting, and polishing. We support custom parts based on your drawings or samples, with tolerances up to ±0.001 mm.