ZrO2 has two kinds of zirconium allotrope cubic structure (c phase), tetragonal structure (t phase) and monoclinic structure (m phase).
According to the composition of the phases contained, zirconia ceramics can be divided into stabilized zirconia ceramic materials and partially stabilized zirconia ceramics.
Stabilized zirconia ceramics
Stabilized zirconia ceramics are mainly composed of cubic phases.
They have high refractoriness, specific heat and thermal conductivity, and are ideal high-temperature insulation materials.
They can be used as linings for high-temperature furnaces and also as various heat-resistant coatings.
Stabilized zirconia ceramics have good chemical stability and are resistant to acid and neutral corrosion at high temperatures,
but are not resistant to alkaline corrosion.
The metals of Groups V, VI, and VII of the Periodic Table of the Elements do not react with them and can be used as a crucible for smelting this metal.
Pure ZrO2 is a good insulator, because of its obvious high-temperature ion conductivity characteristics, can be used as a heating element at 2000℃, a high-temperature electrode material, and also can be used as a lamp for generating ultraviolet rays.
In addition, the oxygen ion conductivity characteristics of stabilized zirconia ceramics can be used to make oxygen sensors for oxygen concentration measurement.
Partially stabilized zirconia ceramics
Partially stabilized zirconia ceramics consist of a tc two-phase structure with very high strength, fracture toughness, and thermal shock resistance, known as “ceramic steel.”
At the same time, its thermal conductivity coefficient is small, thermal insulation effect is good, and thermal expansion coefficient is relatively large, and it is relatively easy to match with metal parts. In the ceramic engine developed recently, it is used for cylinder inner wall, piston and cylinder cover parts.
Partially stabilized zirconia ceramics can also be used as non-lubricated bearings in the mining and minerals industry, nozzles for sandblasting equipment, parts used in the powder metallurgy industry, and punching dies for pharmaceutical applications.
In addition, partially stabilized zirconia ceramics can also be used as a variety of high toughness, high strength industrial and medical devices.
Such as the textile industry drop machine scissors, wool scissors, tape production scissors, microelectronics industry tools.
Zirconia ceramics can also be used as bioceramic materials because they do not react with living organisms.