High purity magnesium oxide (MgO) is an important inorganic non-metallic material with excellent properties such as high temperature resistance, corrosion resistance, electrical insulation, etc. It has a wide range of applications in silicon nitride ceramics.
1. As a sintering aid
Silicon nitride (Si3N4) ceramics is a high-temperature structural material with excellent performance, but its sintering is difficult and densification is difficult. High-purity magnesium oxide can be used as a sintering additive, added to the silicon nitride powder, by reacting with the silicon dioxide on the surface of the silicon nitride powder to generate a silicate liquid phase, lowering the sintering temperature, and promoting the bonding and growth of the silicon nitride particles, to improve the ceramic densification and mechanical properties.
Studies have shown that the addition of appropriate amount of magnesium oxide can make the density, strength, toughness, hardness and other properties of silicon nitride ceramics can be significantly improved, but also improve the thermal conductivity, electrical insulation properties and thermal shock resistance of ceramics.
2. As a toughening agent
High-purity magnesium oxide can also be used as a toughening agent, added to the silicon nitride ceramics, to improve the fracture toughness of ceramics. Magnesium oxide particles can play a toughening role by dispersing in the ceramic matrix and hindering crack extension.
Studies have shown that the addition of magnesium oxide nanoparticles to silicon nitride ceramics can effectively improve the fracture toughness of ceramics, making them less prone to shattering.
3. Other applications
In addition, high-purity magnesium oxide can also be used to prepare other special performance materials for silicon nitride ceramics, such as:
High thermal conductivity silicon nitride ceramics: by adding magnesium oxide particles, the thermal conductivity of silicon nitride ceramics can be improved, so that it has better performance in high temperature thermal conductivity.
Bioactive silicon nitride ceramics: By adding magnesium oxide particles, silicon nitride ceramics can be endowed with good bioactivity so that they can be used as implant materials.
Summarize
High-purity magnesium oxide has an important application value in silicon nitride ceramics, which can significantly improve the performance of ceramics and make them widely used in high-temperature structural materials, cutting tools, wear-resistant materials, biomaterials and other fields. With the deepening of the research, the application of high purity magnesium oxide in silicon nitride ceramics will be more extensive.
