O dióxido de zircónio, com a fórmula química ZrO2, é um cristal branco, inodoro e insípido, insolúvel em água, ácido clorídrico e ácido sulfúrico diluído. É quimicamente inativo e tem elevado ponto de fusão, elevada resistividade, elevado índice de refração e baixo coeficiente de expansão térmica, o que o torna um importante material resistente a altas temperaturas, material de isolamento cerâmico e agente de proteção solar cerâmico, bem como a principal matéria-prima para brocas artificiais.
Uses of zirconia
1.Raw materials for metallic zirconium and its compounds
Used for making metallic zirconium and zirconium compounds, making refractory bricks and crucibles, high-frequency ceramics, abrasive materials, ceramic pigments and zirconates, etc. Mainly used for piezoelectric ceramic products, daily ceramics, refractory materials and precious metal smelting. Zirconium bricks, zirconium tubes, crucibles, etc. Also used in the production of steel and non-ferrous metals, optical glass and zirconium dioxide fibers. Also used in ceramic pigments, electrostatic coatings and baking varnishes. Used in epoxy resins to increase resistance to corrosion by hot salt water.
Zirconia fiber is a polycrystalline refractory fiber material. Due to the high melting point, non-oxidation and other high-temperature properties of the ZrO2 material itself, ZrO2 fiber has a higher service temperature than other refractory fiber varieties such as alumina fiber, mullite fiber, aluminum silicate fiber and so on.
The application of plasma sprayed zirconium dioxide thermal barrier coatings on aviation and industrial gas turbines has made great progress, and has been used in the turbine part of gas turbines to a certain extent. Since this coating can reduce the temperature of air-cooled high-temperature components by 50~200°C, it can significantly improve the durability of high-temperature components, or allow the gas temperature to be increased or the amount of cooling gas required to be reduced while maintaining the temperature of the high-temperature components. changes, thus improving the efficiency of the engine.
4. Ceramic materials
Because of its large refractive index, high melting point and strong corrosion resistance, zirconia is used as a raw material in the kiln industry. Piezoelectric ceramic products include filters, speakers, ultrasonic underwater sound detectors, etc. There are also daily ceramics (industrial ceramic glazes), zirconium bricks and zirconium tubes for precious metal smelting, etc. Nanoscale zirconia can also be used as a matrix material for polishing agents, abrasive grains, piezoelectric ceramics, precision ceramics, ceramic glazes and high-temperature pigments.
In addition, zirconia can be used in the manufacture of incandescent gas lampshades, enamel, white glass, refractory crucibles, etc. X-ray photography. Abrasive materials. Together with yttrium, it is used to manufacture light source lamps in infrared spectrometers, thick film circuit capacitor materials, and piezoelectric crystal transducer formulas.