Ceramics are categorized into functional ceramics and structural ceramics based on performance and application. The functionality of ceramics primarily stems from the unique properties of the material, including electrical, magnetic, biological, thermosensitive, and optical characteristics. This includes insulating and dielectric ceramics, piezoelectric ceramics, semiconductor ceramics, and sensitive ceramics, among others. Structural ceramics are mainly based on the mechanical and structural applications of the material, featuring high strength, hardness, high-temperature resistance, corrosion resistance, and oxidation resistance. They primarily include oxide ceramics, nitride ceramics, carbide ceramics, and boride ceramics.
The properties of structural ceramics are primarily influenced by the crystal structure and crystal defects. In terms of crystal structure, the bonding between atoms in ceramic materials is mainly ionic bonds, covalent bonds, and so on. These chemical bonds possess advantages such as high structural strength and strong directional properties. A notable feature of structural ceramics is the heterogeneity and complexity of their microstructure.
(1) Compared to other metal materials, ceramic materials excel in their superior high-temperature mechanical properties, resistance to chemical corrosion, high-temperature oxidation resistance, and wear resistance. It is due to these performance advantages that ceramics are gradually replacing expensive metal resources in various fields, holding significant value for the development of conserving scarce resources.
(2) Structural ceramics are one of the more suitable materials in the industrial sector for stiffness and hardness. Conventional structural ceramics have high melting points and maintain excellent chemical stability at high temperatures. Moreover, the thermal conductivity of ceramic materials is lower than that of other metals, making them excellent thermal insulators as well.
(3) Most structural ceramics exhibit excellent electrical insulation properties, making them widely used as insulating electrical equipment under various voltages.
(4) Ceramic materials possess unique chemical properties, making them suitable for solid-state laser materials, fiber optics, and optical storage applications. They also hold significant value in various fields, such as recording tapes, vinyl records, and computer storage components.
Structural ceramic materials are primarily used in industrial applications, benefiting from their superior performance and stability, making them widely employed in the automotive manufacturing industry. In recent years, structural ceramics have gradually gained a foothold in the high-tech sector, with their importance continually increasing.
As China's economic level rapidly develops, infrastructure construction has been strengthened. Structural ceramics, as the main application material in the mechanical industry, is also facing increasingly fierce market competition during its rapid development. Currently, metal is the most commonly used material in various fields in our country, with a history of over a century of development. Although it has been repeatedly improved, due to its inherent limitations, it gradually fails to meet the requirements of wear and corrosion resistance, severely affecting the operational stability of various application systems. Structural ceramics, however, possess significant performance advantages and are poised to become the main application material in various fields, with a promising development outlook.
