The properties of zirconia ceramics:
pure ZrO2 is white, yellow or gray when it contains impurities, and generally contains HfO2, which is not easy to separate. The world’s proven zirconium resources are about 19 million tons, and zirconium oxide is usually made from zirconium ore.
zirconia ceramic structural parts
There are three crystal states of pure ZrO2 under normal pressure: Monoclinic zirconia (m-ZrO2), Tetragonal zirconia (t-ZrO2) and Cubic zirconia (c-ZrO2). The three crystal forms exist in different temperature ranges and can be transformed into each other:
Monoclinic Zirconia (m-ZrO2) <950℃ 5.65g/cc
Tetragonal zirconia (t-ZrO2) 1200-2370℃ 6.10g/cc
Cubic zirconia (c-ZrO2) >2370℃ 6.27g/cc
The above three crystal states have different physical and chemical properties. In practical applications, in order to obtain the required crystal form and performance, different types of stabilizers are usually added to make different types of zirconia ceramics, such as partially stabilized zirconia (partially stabilized zirconia, PSZ), when the stabilizer is CaO, MgO, Y2O3, they are respectively represented as Ca-PSZ, Mg-PSZ, Y-PSZ, etc. The tetragonal zirconia composed of metastable t-ZrO2 is called tetragonal zirconia polycrysta (TZP). When the added stabilizer is Y2O3, CeO2, they are expressed as Y-TZP, Ce-TZP, etc. respectively.
Application of Zirconia Ceramics:
In terms of structural ceramics, zirconia ceramics are widely used in the field of structural ceramics due to their high toughness, high bending strength and high wear resistance, excellent thermal insulation properties, and thermal expansion coefficient close to steel. Mainly include: Y-TZP grinding balls, dispersion and grinding media, nozzles
, ball valve seats, zirconia molds, micro fan shafts, optical fiber pins
, optical fiber sleeves, drawing dies and cutting tools, wear-resistant knives, clothing buttons, Watch cases and straps, bracelets and pendants, ball bearings, light golf batting sticks and other room temperature wear-resistant parts.
In terms of functional ceramics, its excellent high temperature resistance is used as induction heating tubes
, refractory materials, and heating elements. Zirconia ceramics have sensitive electrical performance parameters and are mainly used in the fields of oxygen sensors, solid oxide fuel cells (Solid Oxide Fuel Cell, SOFC) and high temperature heating elements. ZrO2 has a high refractive index (N-21^22). Adding certain coloring elements (V2O5, MoO3, Fe2O3, etc.) to the ultrafine zirconia powder can be made into a colorful translucent polycrystalline ZrO2 material , Shining brilliantly and colorfully 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, refractory materials, textiles and other fields.
The advantages of zirconia ceramics:
Compared with metals, zirconia ceramics have higher hardness, wear resistance, corrosion resistance, and high temperature resistance than metals. Its high temperature performance is unmatched by metals. As for the use, it mainly depends on the demand.
Zirconia ceramics will replace traditional metals and become the new favorites of all major industries. High performance determines this. According to the prediction of the national department, the future market of zirconia is trillion level, and the prospect is broad. At present, a large number of industries have adopted zirconia as the first material.