Silicon nitride bonded silicon carbide brick is a high-performance refractory material widely used in metallurgy, ceramics, chemical industry and other fields. Its performance is affected by many factors, among which molding volume density is one of the key factors affecting its performance. This article will explore the influence of molding volume density on the performance of silicon nitride bonded silicon carbide bricks from the following aspects.
1. Definition of molding volume density
Molded bulk density refers to the density of silicon nitride combined with silicon carbide bricks during the sintering process. It reflects the size of the internal porosity of the material and directly affects the mechanical and thermal properties of the material.
2. Effect of molding volume density on mechanical properties
As the molding volume density increases, the mechanical properties of silicon nitride bonded silicon carbide bricks gradually improve. Bricks with high volume density have higher flexural strength and compressive strength. This is mainly because the increase in density reduces the internal porosity of the material and enhances the structural strength of the material.
3. Effect of molding volume density on thermal properties
The molded bulk density also has an important influence on the thermal properties of silicon nitride bonded silicon carbide bricks. As the volume density increases, the thermal conductivity of the material gradually decreases, and the thermal expansion coefficient also gradually decreases. This indicates that bricks with high volume density have better thermal shock resistance and thermal stability.
4. Effect of molding volume density on weather resistance
The molded bulk density also affects the weather resistance of silicon nitride bonded silicon carbide bricks. At high temperatures, the pores in the bricks easily absorb gas and water vapor, causing the surface of the bricks to be corroded and oxidized. Bricks with high bulk density have less exposed surface and less porosity, and therefore have better weather resistance.
In summary, the molded bulk density has an important influence on the performance of silicon nitride bonded silicon carbide bricks. In order to obtain high-performance silicon nitride bonded silicon carbide bricks, the molding volume density should be optimized by controlling the sintering process parameters and the density of the material should be improved to obtain better mechanical properties, thermal properties and weather resistance.
