Properties of zirconia ceramics: pure ZrO2 is white, yellow or gray when it contains impurities, and generally contains HfO2, so it is not easy to separate. There are about 19 million tons of zirconium resources in Bai in the world. Zirconia is usually made from zirconium ore. At atmospheric pressure, pure ZrO2 has three crystal states: monoclinic zirconia (m-ZrO2), tetragonal zirconia (t-ZrO2) and cubic zirconia (c-ZrO2)
Temperature density
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
Zirconia ceramic disk
In practical application, 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 (PSZ). When the stabilizers are Cao, MgO, Y2O3, they are respectively expressed as Ca PSZ, Mg PSZ, y-psz, etc. Tetragonal zirconia polycrysta (TZP) is composed of metastable t-ZrO2. When the stabilizers are Y2O3 and CeO2, they are Y-TZP and CE TZP respectively.
Zirconia ceramic structural parts
Zirconia ceramic applications:
In the aspect of structural ceramics, zirconia ceramics are widely used in the field of structural ceramics because of its high toughness, high bending strength, high wear resistance, excellent thermal insulation performance and thermal expansion coefficient close to that of steel. It mainly includes: Y-TZP grinding ball, dispersion and grinding medium, nozzle, ball socket, zirconia mold, micro fan axis, optical fiber pin, optical fiber sleeve, drawing die and cutting tool, wear-resistant tool, clothing button, watch case and strap, bracelet and pendant, ball bearing, light ball bat of golf ball and other wear-resistant components at room temperature.
In the aspect of functional ceramics, its excellent high temperature resistance is used as induction heating tube, refractory and heating element. Zirconia ceramics have sensitive electrical properties and are mainly used in oxygen sensors, solid oxide fuel cells (SOFC) and high temperature heaters. ZrO2 has a high refractive index (n-21 ^ 22). Adding some coloring elements (V2O5, MoO3, Fe2O3, etc.) to the ultra-fine zirconia powder, it can be made into colorful translucent polycrystalline ZrO2 materials, which can be made into various ornaments with brilliant light like natural gemstones. In addition, zirconia is widely used in thermal barrier coating, catalyst carrier, medical treatment, health care, refractory, textile and other fields.
Advantages: zirconia ceramic is higher than metal in hardness, wear resistance, corrosion resistance, and high temperature resistance than metal. Its high temperature performance is unmatched by metal, and its application mainly depends on demand.
Zirconia ceramics will replace the traditional metals and become the new favorite of all major industries. High performance determines this point. According to the prediction of the State Department, zirconia will have a trillion level market in the future, with broad prospects. At present, a large number of industries have adopted zirconia as the first material.