Background requirements for advanced industrial precision ceramic materials:
With the rapid development of modern science and technology, it is urgent to White Zirconia Ceramic research and develop a new generation of ceramic materials with special properties. This is because advanced ceramic materials combined by ionic bonds and covalent bonds have advantages that metal materials and other polymer materials do not have. High modulus, high hardness, wear resistance, high temperature resistance, corrosion resistance, erosion resistance, good biocompatibility and excellent electrical, optical, magnetoelectric, piezoelectric, pyroelectric and other characteristics. As a result, it has been used more and more in many fields such as aerospace, national defense and military industry, mechanical chemical industry, biomedicine, information electronics, nuclear power and new energy, and has become an indispensable key material in some major national projects and cutting-edge technologies. Therefore, it has important scientific value and national strategic significance.
In the past two decades, higher requirements have also been placed on ceramic materials and their preparation technologies in major national projects and cutting-edge Machinable Ceramic technologies. Under the conditions of high-speed operation without slippage, ceramic bearings are required to have high strength, wear resistance, good toughness and high surface machinability. Laser weapons need to use high-power and large-size Nd-YAG laser transparent ceramics, missile radomes need to use high-transmission and high-strength ceramic materials, and large-size ceramic sealing rings used in the main pump of nuclear power plants need long life and high reliability. In particular, the silicon carbide ceramic mirrors used in the ground monitoring of the ground targets for the earth satellites, in addition to high elastic modulus, low thermal expansion coefficient and small specific gravity, require high precision, surface such as mirror surface and large size (diameter: 1 meter to several meters) , which is a challenge to the forming technology, sintering technology and processing technology of large-scale structural ceramic materials. Another example is the micro-ceramic cleaver used in the microelectronics industry, whose inner hole is only 20-30 microns, while the optical fiber connector ceramic ferrule in optical communication has an inner hole of 125 microns, and requires extremely high surface finish and Dimensional accuracy and concentricity.
In addition, the rapid development of ultra-high temperature structural Macor Ceramics ceramics (such as ZrB2, HfB2) and ceramic composites (Cf/SiC, SiCf/SiC) enables the space shuttle to return to Earth after entering space. B4C ceramics become an indispensable control rod for absorbing neutrons in the reactor. High hardness ceramic tools are more efficient (3~10 times) than traditional tools. Si3N4 Ceramic Tubes and SiC ceramics, as high-temperature key components of engines and gas turbines, can increase the turbine inlet temperature to 1370 °C, which can greatly improve thermal efficiency and save fuel. more and more. In high-speed rail and electric vehicles, the demand for high-performance AIN ceramic substrates and Si3N4 ceramic substrates with high strength, high toughness and high thermal conductivity is increasingly urgent for IGBT power control module packaging. Automotive diesel vehicles require honeycomb ceramics and catalyst carriers with better performance, thereby greatly reducing the pollution of vehicle exhaust emissions to the environment.
These examples fully demonstrate that advanced ceramic materials are essential to the development of modern science and engineering technology. Especially in the past ten years, due to various high-purity oxide ceramics (AI2O3, ZrO2, SiO2, MgQ, Y2O3, MgAI204), nitride ceramics (Si3N4, BN AIN, AION), etc., Silicon Nitride Parts carbide ceramics (SiC, B4C), etc. , The preparation technology of boride ceramics (TiB2, ZrB2, HfB2) and other ceramic materials and the development of nano-ceramic composite technology, the various Silicon Nitride Ceramics mechanical properties, thermal properties, light and wave transmission properties of a new generation of ceramic materials have been greatly improved, and the application field is more Expansive and impressive.
Why use precision ceramics?
2022 06/16