Application of silica sol in refractory materials

1. As a binder

Silica sol has strong bonding force and high temperature resistance, and can remain stable at high temperatures, so it is widely used as a binder for various refractory materials. For example:

In the manufacture of ceramic furnaces, silica sol can be used as a binder for ceramic fibers. The aluminum silicate fiber felt is impregnated with silica sol to make insulation felt, which plays a role in heat preservation

and insulation.

Silica sol can also be used as a binder for acid-resistant cement, various thermal insulation materials and silicate materials, with the characteristics of strong bonding force, acid resistance and high temperature resistance.

When manufacturing silicon steel, silica sol can be used as a binder to bond silicon steel sheets into one, which plays a role in insulation and high temperature resistance.

2. Improving the performance of refractory materials

Silica sol can increase the density and thermal shock resistance of refractory materials, and prevent the expansion, cracking or deformation of refractory materials caused by high temperature.

At the same time, it can further improve the stability of the material, so that it can maintain the same material structure under extreme conditions. The specific performance is as follows:

High temperature resistance: Silica sol can maintain structural stability, reduce thermal expansion and thermal stress of materials, and improve the durability and life of refractory materials.

Compressive and shear strength: Silica sol can fix refractory particles, form a tight structure, and increase the compressive and shear strength of materials.

Density and hardness: Silica sol can fill the gaps between materials, increase the density and hardness of materials.

Chemical erosion resistance: Silica sol can block the erosion of corrosive media such as acids and alkalis in refractory materials, and the protective layer formed can improve the chemical erosion resistance

of materials.

3. Application in the foundry industry

Silica sol also has important applications in thin shell precision casting.

It can improve the strength and casting finish of the shell mold, and has better molding quality than water glass,

and can reduce costs and improve operating conditions. The thin shell made of small-particle silica sol instead of ethyl silicate has high strength and good finish,

which can greatly improve the quality and dimensional precision of castings.

4. Other applications

In addition to the above applications, silica sol can also be used to make high-temperature protective layer coatings.

Mixing silica sol with refractory powder (such as silicon oxide, aluminum oxide, zirconium oxide, iron oxide, etc.)

and coating it on the surface of heat-resistant and corrosion-resistant containers can form a high-temperature resistant protective layer to protect the working surface of the mold and the bottom plate,

greatly reduce the loss of the mold, and make it demold well.

In summary, the application of silica sol in refractory materials is very extensive and important. It can not only improve the performance and service life of refractory materials,

but also reduce production costs and improve operating conditions.

With the advancement of science and technology and the development of industrial production, the application of silica sol in the field of refractory materials will become more and more extensive.