Silicon nitride ceramic products are what we focus on as high-temperature structural materials used in harsh conditions. Especially its most glamorous prospect for an all-ceramic engine. Therefore, it is not only necessary to make the performance of the material as stable as possible, but also to ensure the mechanical reliability of the product. For this reason, in addition to further in-depth theoretical research, as a production unit, it must keep in mind and achieve "pure, fine, dense, and homogeneous" under permitted conditions. These five words are not only the general technical requirements, but also the trend of industrial technology development.

1. Pure means that the raw materials are as pure as possible, harmful impurities are removed as much as possible, and harmful impurities are avoided as much as possible during the whole preparation process. The fired ceramic body has fewer grain boundary phases and the phase composition is as simple as possible.
2. Fine means that the split particle size of the solid raw material and the intermediate composition should be fine, and the grain size of the fired ceramic body should be fine.
3. Dense means that the formed green body is as dense as possible, the sintering is as complete as possible, the porosity of the fired ceramic body is as low as possible, and the bulk density is as close to the theoretical density as possible.
4. Homogeneous means that the particle distribution range of the powder should be narrow. From forming the green body to firing the ceramic body, it is necessary to prevent the concentration of thermal stress and mechanical stress, prevent asynchronous sintering, minimize the defects in the ceramic body, and avoid anisotropy.

The industrial production of silicon nitride ceramics is absolutely not limited by resources. The synthesis of silicon nitride can be carried out in various ways, and the original source is generally very easy. For more than 20 years, the preparation industry of silicon nitride ceramics has been continuously improved, the production scale has been continuously expanded, the cost has gradually decreased, and the market demand has also doubled. Therefore, silicon nitride ceramics have obvious potential competitive power in the field of new materials and have great development prospects.