In recent years, the development of many new technologies has put forward higher requirements for ceramic materials, which need to have high thermal stability, corrosion resistance, high mechanical strength and good high-temperature insulation properties. Among the materials that meet these requirements, aluminum nitride ceramics are considered one of the most promising. According to the literature, the density of ceramics made of aluminum nitride powder during hot pressing is close to the theoretical value. However, the hot pressing method is limited in the production of complex shapes and large parts. What factors affect the density of aluminum nitride ceramics? This is a question that needs to be deepened.
In the ceramic industry, with the continuous development of technology, the scale of many enterprises continues to expand, and the quality of products is also improving. As one of them, the preparation technology of aluminum nitride ceramics is becoming more and more mature. It can be divided into two categories, one is ceramics with very pure aluminum nitride content, which can reach a sintering temperature of 1800 degrees Celsius, and can even replace platinum, which can be used as an insulating material. The other is the ordinary type classified according to the different aluminum nitride content, which can be used to make high-temperature resistant crucibles, ceramic valve plates, bearings, etc. What is the influence on the density of aluminum nitride ceramics depends on the properties of aluminum nitride itself.
Chemically, aluminum nitride is a chemical compound, but processedly, it can only be used as a material because there are many impurities mixed in it, and it is not pure aluminum nitride. Aluminum nitride has a high hardness and is an amphoteric oxide that is prone to reaction and ionization, so it is suitable for use as a refractory material. High-temperature sintering is required in the production of ceramics, and the choice of aluminium nitride is a compound that can avoid damage during the manufacturing process.
After the aluminum nitride ceramics have been molded, the required density is often not achieved when they are processed with high purification. At this point, it is necessary to consider whether there is a problem with the raw powder and formulation. If there is no problem with the root cause, you can try to increase the pressure and increase the sintering temperature. However, it is not advisable to extend the holding time during the high-purification process, as this may lead to deformation of the internal grains of the aluminum nitride. Ideally, the grains need to be homogeneous in order to guarantee good performance of their microstructure.