Zirconia ceramics are advanced ceramic materials with zirconium oxide (ZrO₂) as the main component. The following will introduce its characteristics, types, production processes, and application fields in detail:
Basic characteristics
Mechanical properties: It has high hardness, high strength, and high toughness. Its hardness is second only to superhard materials such as diamond and cubic boron nitride. It performs well in wear resistance and impact resistance.
Thermal properties: The melting point is as high as 2715℃, with good high temperature resistance and thermal insulation performance. At the same time, the thermal expansion coefficient is similar to that of metal, and it can maintain stable size and performance under different temperature environments.
Electrical properties: It is a good insulator at room temperature, and has certain ionic conductivity under high temperature or specific doping conditions. It can be used to manufacture solid oxide fuel cells, oxygen sensors, and other devices.
Chemical properties: It has excellent chemical stability, is resistant to corrosion by chemicals such as acids, alkalis, and salts, and can maintain stable performance in harsh chemical environments.
Production process
Raw material preparation: Zirconium oxide is extracted from zirconium ore, and high-purity zirconium oxide powder is obtained after purification. Common purification methods include chlorination and thermal decomposition, alkali metal oxidation decomposition, lime melting, etc.
Molding: Including dry pressing, isostatic pressing, slip casting, hot die casting, tape casting, etc. Among them, dry pressing is suitable for manufacturing products with simple shapes and large sizes; slip casting is suitable for preparing large ceramic parts with complex shapes; tape casting is often used to prepare film materials.
Degreasing and debinding: In addition to dry pressing, other molding processes will add a certain proportion of plasticizer during molding. After molding, the plasticizer needs to be removed by heating and other methods to avoid affecting the quality of the sintered product.
Sintering: Pressureless sintering, hot pressing sintering, hot isostatic pressing (HIP), microwave sintering and other methods can be used to sinter the green body into a dense ceramic product at high temperature. Accurately controlling parameters such as sintering temperature, insulation time and sintering atmosphere is crucial to obtaining zirconia ceramics with excellent performance.
Application fields
Industrial manufacturing field
In mechanical manufacturing, it is used to manufacture high-precision bearings, seals, etc. Zirconia ceramic bearings have the characteristics of low friction coefficient, high precision and long life, and can be used in high-speed and high-temperature mechanical operation environments, such as high-speed machine tool spindles, aircraft engines and other equipmen.
In the chemical industry, it is used to manufacture various corrosion-resistant pipes, valves, pump liners, etc. These ceramic components can effectively resist the corrosion of strong acids, strong alkalis, and other chemical substances, ensuring the continuity and safety of chemical production.
Electronic field
As a substrate material for electronic components, zirconia ceramics can provide good insulation and heat dissipation properties for electronic chips, etc. In the semiconductor manufacturing process, it is used to manufacture some components in high-temperature and high-cleanliness environments, such as wafer carriers.
Biomedical field
In addition to the dental applications mentioned above, it is also used in orthopedics. For example, it is used to manufacture artificial joint heads, etc. Its good wear resistance and biocompatibility can reduce the adverse effects of debris generated by joint wear on surrounding tissues, and can coexist with human bone tissue for a long time.
Aerospace field
Used to manufacture high-temperature components of aircraft engines, such as thermal barrier coatings. These coatings can reduce the actual operating temperature of engine components, improve the thermal efficiency and performance of the engine, and extend the service life of engine components.
In short, zirconia ceramics play an increasingly important role in modern industry and technology with their many excellent properties.
