Silicon nitride ceramics is a class of materials with the best comprehensive performance in the structural ceramics family, and is considered to be one of the most promising high-temperature structural ceramic materials for development and application. Silicon nitride ceramics have high flexural strength and fracture toughness, such as silicon nitride ceramics prepared by hot pressing sintering, at room temperature, the flexural strength can reach 800-1050MPa, and the fracture toughness can reach 6-7MPa m ^{1/ 2} , and has good wear resistance and certain self-lubricating ability. Therefore, silicon nitride is well suited for bearing material applications. In addition, silicon nitride ceramics also have a relatively high theoretical thermal conductivity, which makes it considered as a potential heat dissipation and packaging material for high-speed circuits and high-power devices.

The initial application of silicon nitride ceramics is 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 development of manufacturing industry and testing and analysis technology, the reliability of silicon nitride ceramic products has been continuously improved, so the application area is constantly expanding. The main contents of the application are as follows:

1. In the metallurgical industry, it can be made into parts of thermal equipment such as tongs, muffle furnace, burner, heating body fixture, casting mold, and aluminum liquid conduit.
2. In the machinery industry, high-speed turning tools, bearings, heat-treated supports for metal parts, rotor engine scrapers, guide vanes and turbine blades for gas turbines, etc. are made.
3. In the chemical industry, ball valves, pump bodies, sealing rings, filters, heat exchanger components, immobilized catalyst carriers, combustion boats, evaporators, etc. are made.
4. In semiconductor, aviation, atomic energy and other industries, it is used to manufacture switch circuit substrates, film capacitors, electrical insulators that withstand high temperature and drastic temperature changes, radar radomes, missile tail nozzles, supports and separators in atomic reactors, nuclear fission material carrier, etc.
5. Artificial joints can be made in medical engineering companies.
6. The silicon nitride all-ceramic engine under development replaces the same type of metal engine.