Silicon nitride (Si3N4) ceramics have the advantages of high specific strength, high specific modulus, high-temperature resistance, oxidation resistance and wear resistance, and thermal shock resistance.
The initial application of silicon nitride ceramics was mainly used in machinery, metallurgy, chemical industry, aviation, semiconductor, and other industries, as parts of certain equipment or products, and achieved good expected results. In recent years, with the manufacturing process and test analysis with the development of technology, the reliability of silicon nitride ceramic products has been continuously improved. The main contents of related applications include high-speed turning tools in the machinery industry, bearings, supports for heat treatment of metal parts, rotor engine blades, gas turbine guide vanes turbine blades, etc.
Because of its superior mechanical, chemical, electrical, optical, and thermal properties, traditional silicon nitride ceramics are made of large-grained, multi-phase powder sintered, so they have high brittleness, poor uniformity, low reliability, toughness, and strength are very poor, and its application is greatly limited. Nano-silicon nitride has the following characteristics: extremely small particle size, large specific surface area and high chemical properties, which can significantly improve the densification of silicon nitride ceramics during the sintering process. It can reduce the sintering temperature and save energy; and can make the composition and structure of silicon nitride ceramics uniform, improve the performance of the material, and improve its reliability.
With the advancement of science and technology, metallurgical enterprises are increasingly developing in the direction of large-scale, continuous, automated, pollution-free, low-consumption, etc. Therefore, metallurgical enterprises must adopt new technologies, new equipment, and new materials in many materials. The carbon nitride ceramic materials produced by silicon and silicon nitride composites are continuously used by metallurgical enterprises all over the world and are also more and more widely used in the metallurgical industry.
Silicon nitride ceramics are high-temperature ceramics with high-temperature strength, high hardness, wear resistance, corrosion resistance, and self-lubricating properties. The coefficient of linear expansion is the smallest among various ceramics. In addition to hydrofluoric acid, it is resistant to corrosion by other acids, alkali, and various metals, and has excellent electrical insulation and radiation resistance. It can be used as a high-temperature bearing and a sealing ring used in corrosive media, Thermowell, can also be used as a metal cutting tool.
Ceramic materials used in automobile engines, energy-saving and emission-reducing automobiles are obtained by using high-purity and ultra-fine oxides, nitrides, borides, and other raw materials through special processes such as pretreatment, crushing, grinding, mixing, forming, drying, and sintering. Inorganic non-metallic material with fine structure. It has a series of advantages such as high strength, high heat resistance, corrosion resistance, high hardness, high wear resistance, low density, small deformation, thermal shock resistance, especially tensile strength and bending strength of silicon nitride is comparable to that of metal. Silicon nitride belongs to structural ceramics. The quality of structural ceramics is half that of iron. The energy-saving effect is very significant. At the same time, it can also reduce environmental pollution and save metal materials such as steel.
The initial application of silicon nitride ceramics was mainly used in machinery, metallurgy, chemical industry, aviation, semiconductor, and other industries, as parts of certain equipment or products, and achieved good expected results. In recent years, with the manufacturing process and test analysis with the development of technology, the reliability of silicon nitride ceramic products has been continuously improved, so the application area is constantly expanding. Or electrical insulators with dramatic temperature changes, randoms, missile tail nozzles, supports and spacers in atomic reactors, carriers of nuclear fission materials, etc.
Silicon nitride Si3N4 ceramics has excellent comprehensive properties and abundant resources, is an ideal high-temperature structural material, has a broad application field and market, and all countries in the world are competing for research and development. Ceramic materials have the characteristics of wear resistance, corrosion resistance, high-temperature resistance, oxidation resistance, thermal shock resistance, and low specific gravity that are incomparable with general metal materials. Metal materials and polymer materials have become the key basic materials to support the pillar industry in the 21st century. There are also many types of silicon nitride ceramic products, and their applications are becoming more and more extensive.