Zirconia ceramics are white, yellow or gray when containing impurities, and generally contain HfO 2, which is difficult to separate. There are three crystalline states of pure ZrO2 at atmospheric pressure. The production of zirconia ceramics requires the preparation of high purity, fine dispersion, ultrafine particles and narrow particle size distribution. Zirconia ultrafine powders are prepared by many methods, such as chlorination and thermal decomposition, alkali metal oxidation, lime melting, plasma arc, precipitation, colloid, hydrolysis, spray pyrolysis, etc.
In structural ceramics, zirconia ceramics are widely used in structural ceramics because of their high toughness, high flexural strength, high wear resistance, excellent thermal insulation and thermal expansion coefficient close to steel. Mainly: Y-TZP grinding ball, dispersing and grinding medium, nozzle, ball valve seat, zirconia mould, micro fan axis, optical fiber insert, optical fiber sleeve, wire drawing die and cutting tools, wear-resistant tools, clothing buttons, watch case and strap, bracelet and pendant, ball bearing, golf ball lightweight bat and other room temperature wear-resistant parts.
In the aspect of functional ceramics, its excellent high temperature resistance is used as induction heating tubes, refractories and heating elements. Zirconia ceramics have sensitive electrical properties, which are mainly used in oxygen sensors, solid oxide fuel cells (SOFC) and high temperature heaters. ZrO 2 has a high refractive index (N-21^22). By adding certain coloring elements (V2O5, MoO 3, FeO 3, etc.) to the superfine zirconia powder, it can be made into a multicolored translucent polycrystalline ZrO 2 material, which shines like natural gemstones and can be made into various decorations. In addition, zirconia is widely used in thermal barrier coatings, catalyst carriers, medical treatment, health care, refractories, textiles and other fields.