The scientific name of zirconia is zirconia, and its molecular formula is ZrO2. It is the main oxide of zirconium. The minerals containing zirconium in nature mainly include baddeleyite and zircon. Zirconia is usually a white odorless and tasteless crystal, insoluble in water, hydrochloric acid, and dilute sulfuric acid, chemically stable, and has the characteristics of high hardness, high melting point, high resistivity, high refractive index, and low thermal expansion coefficient. Wear-resistant ceramics, refractory materials, machinery, electronics, optics, aerospace, biology, chemistry, etc. have been widely used in various fields. Our common artificial drills and dental implants also use zirconia as the main material.
Properties of Zirconia
1. High hardness: The hardness of zirconia products can usually reach more than 7.5 on the Mohs scale, and the hardness of some products such as zirconia ceramics can exceed 9, second only to diamond. High hardness means that it has strong wear resistance, so zirconia ceramics are good wear-resistant materials.
2. High melting point: The melting point of zirconia is as high as 2715°C, and its chemical properties are stable. It is an excellent refractory material.
3. Low thermal conductivity and low expansion coefficient: The thermal conductivity of zirconia is relatively low among common materials (1.6-2.03W/(m.k)), and the thermal expansion coefficient is close to that of metal. Therefore, zirconia ceramics are suitable for official ceramic materials, such as zirconia ceramic mobile phone exterior structural parts.
4. Special conductivity: Zirconia does not conduct electricity at room temperature, and its resistivity is extremely high. However, in a high-temperature environment, zirconia has certain conductivity. Using this principle, zirconia is also used in many electronic devices.