Characteristics and application of thermal conductivity of zirconia ceramics
What is the thermal conductivity of zirconia ceramics?
The thermal conductivity of zirconia ceramics refers to the characteristics of zirconia ceramic materials in terms of heat conduction, that is, the ratio of the unit area of the object through which heat passes through per unit time to the temperature difference during heat conduction.
Characteristics of thermal conductivity of zirconia ceramics
The thermal conductivity of oxide ceramics is very low, usually only a few tenths of that of metals, so oxide ceramics are an insulating material. At the same time, oxide ceramics also have the characteristics of heat resistance, corrosion resistance, high hardness and high strength.
In addition, the thermal conductivity of oxide ceramics has very little effect on temperature, so it can still maintain good insulation performance in high temperature environments.
Application of thermal conductivity of zirconia ceramics
Due to the low thermal conductivity of zirconia ceramics, insulators, bushings and other components made of zirconia ceramics can ensure the safety and reliability of electrical equipment under high temperature, high pressure, strong electric field and other environments. Zirconia ceramics are also widely used in aerospace, aviation, military and other fields.
In addition, zirconia ceramics are often used to make thermal barrier coatings, sintered particles, friction materials, etc. Due to their good wear resistance and excellent wear performance, they are widely used in the field of machinery manufacturing.
Breakdown Mechanism of Thermal Conductivity of Zirconia Ceramics
The low thermal conductivity of oxide ceramics is actually due to their microstructure. In zirconia ceramics, the oxygen vacancies at the grain boundaries can act as the free moving centers of carriers, resulting in the local enhancement of thermal current and electric field on the surface of zirconia ceramics. When the strength of this local area exceeds the breakdown electric field of the zirconia ceramic, arc breakdown occurs.
How to improve the thermal conductivity of zirconia ceramics?
Aiming at the problem of low thermal conductivity of oxide ceramics, researchers have proposed some methods. First, zirconia ceramics with different thermal conductivity were prepared through microstructure regulation. The second is to combine zirconia ceramics with conductive materials, and use the conductive layer to regulate the thermal conductivity of zirconia ceramics.
Characterization method of thermal conductivity of zirconia ceramics
When researching and preparing the thermal conductivity of oxide ceramics, it is necessary to use some specific test methods to characterize its thermal conductivity. Such as common thermal conductivity tester, thermocouple temperature measurement system and other instruments.
The thermal conductivity of oxide ceramics is very low, even lower than that of metals. This makes them excellent insulating properties at high temperatures since not much heat can escape. However, low thermal conductivity is also subject to certain limitations, such as their poor ability to dissipate heat. Therefore, a trade-off between thermal conductivity and other properties is required in practical applications. When I tested the thermal conductivity numbers of oxide ceramics in the lab, I realized that these ceramics have a wide range of applications in research and development. Whether it is in the manufacture of high-temperature furnaces, wear-resistant parts, aerospace or electronic devices, it can play an important role. I deeply love working with ceramics because it makes me feel like I am working towards a better future. I believe that constantly exploring the thermal conductivity and other properties of zirconia ceramics will bring me new discoveries and achievements. Due to the breakdown problem of zirconia ceramics, it is necessary to pay attention to its repair and maintenance in practical application.