Alumina ceramics, also known as alumina or aluminium oxide (Al2O3), are a type of industrial oxide ceramics known for their extremely high hardness and high thermal conductivity. The properties of alumina ceramics make them one of the most widely used ceramics in structural, wear and corrosive environments.

Alumina ceramics are typically made from bauxite and can be molded using injection molding, molding, isostatic pressing, grouting, diamond processing and extrusion. Like aluminum nitride and other important engineering materials, alumina can be produced by dry pressing and sintering or hot pressing with appropriate sintering aids.

Alumina ceramics are among the most studied and characterized advanced ceramic materials known today. Their behavior has been thoroughly studied due to the important combination of properties. Alumina is characterized by high hardness, corrosion resistance, good thermal stability, good dielectric properties (for conversion from DC to GHz frequencies), low loss angular tangent and stiffness.

Depending on the content of Al2O3 and the additives used, there are different series of alumina materials.

• According to Al2O3 content, alumina can be classified as 75% alumina, 85% alumina, 95% alumina, 99% alumina, 99.5% alumina and so on.
• Depending on the crystalline phase, there are mullite, corundum-mullite, and corundum;
• Depending on the type of additive used, there are chrome corundum, titanium corundum, etc.

1.     Aluminum oxide is an excellent electrical insulator, resisting very high currents, and its electrical resistance increases with its purity. The higher the purity of the aluminum oxide, the higher the resistance.
2. Aluminum oxide ceramics have a very high melting point and strong mechanical strength. However, its mechanical strength decreases at temperatures above 1000 degrees Celsius. Due to the large difference in its coefficient of thermal expansion, its resistance to thermal shock is less effective when exposed to very high temperatures.
3. The excellent chemical stability of aluminum oxide is the main reason for its high corrosion resistance.
4. Aluminum oxide is also slightly soluble in strong acids (e.g., hot sulfuric acid and hot HCl and HF are also somewhat corrosive) and alkaline solutions, but insoluble in water. Pure alumina is resistant to chemical corrosion, making pure alumina the primary choice for engineered components in a wide variety of industrial applications. Its resistance to chemical corrosion has been shown to be due to its low solubility in these chemicals.
5. Additives are introduced to enhance the physical and chemical properties of alumina. These additives, in combination with different production processes, can help produce alumina ceramics of different sizes and shapes.
6. Alumina ceramic materials have the lowest vapor and decomposition pressures.
7. Alumina ceramics are similar to aluminum nitride based on their good thermal conductivity and good electrical insulation properties.

1. Alumina ceramics are widely used in acid-resistant pump impellers, pump bodies, acid-carrying pipe linings and valves because of their excellent chemical stability.
2. Alumina ceramics are used in the manufacture of textile wear parts and knives. This is due to their extremely high hardness and wear resistance.
3. Aluminum oxide ceramic materials are used in the manufacture of spark plugs, which can be used in a variety of engines.
4. Aluminum oxide ceramics are used to make high-pressure sodium lamps and infrared detection window materials.
5. Alumina ceramics with an alumina content higher than 95% are used as excellent electrical insulators. They also have low dielectric loss and have a wide range of applications in electronics and appliances.
6. Transparent aluminum oxide exhibits good permeability to visible and infrared light.
7. Other important applications for alumina ceramics can be seen in sealing rings, medical prosthetics, laser tubes, thermocouple tubes, electronic substrates, ballistic armor, electrical insulators, abrasive media and wear parts.

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Alumina ceramics consist of aluminum oxide. The high thermal conductivity, high heat resistance, excellent electrical insulation properties and high chemical resistance of alumina materials are some of the factors that make them the material of choice for many industrial processes.

To Good Ceramics is a professional aluminum oxide ceramics processing manufacturer. Since 2013, we have participated in and supplied more than 3,000 precision ceramic products to hundreds of companies. We can provide you with ceramic machining, ceramic materials, ceramic casting, ceramic metal encapsulation and surface metallization services, and we are committed to providing products and services that meet or exceed our customers' quality requirements.

To Good Ceramics is your custom machining specialist for aluminum oxide ceramics, and we can meet your advanced ceramic prototyping needs. We are always happy to utilize our years of advanced ceramics experience to advise on materials, designs and applications. If you are looking to purchase alumina plates, rods, tubes, or custom machined parts, please contact us and each of our experts will be happy to assist you.