Refractory materials are usually classified according to their chemical composition, refractoriness, shape and manufacturing process. The following are the main classification methods:
1. Classification by chemical composition:
Acidic refractories: The main component is silicon dioxide (SiO₂), such as silica bricks, clay bricks, etc. This type of material is suitable for acidic environments, but not suitable for contact with alkaline substances.
Alkaline refractories: The main component is magnesium oxide (MgO) or calcium oxide (CaO), such as magnesia bricks, dolomite bricks, etc. This type of material is suitable for alkaline environments.
Neutral refractories: The main component is bauxite (Al₂O₃) or silicon carbide (SiC), such as high alumina bricks, silicon carbide bricks, etc. This type of material is suitable for acidic and alkaline environments.
2. Classification by refractoriness:
Ordinary refractories: The refractoriness is between 1580°C and 1770°C, such as ordinary clay bricks.
Advanced refractory materials: Refractory degree is between 1770°C and 2000°C, such as high alumina bricks, silica bricks, etc.
Special grade refractory materials: Refractory degree is above 2000°C, such as zirconium corundum bricks, silicon carbide bricks, etc.
3. Classification by shape and structure:
Shaped refractory materials: Refractory materials with standard shapes, such as bricks, blocks, etc.
Amorphous refractory materials: Refractory materials without fixed shapes, such as castables, ramming materials, refractory coatings, etc.
4. Classification by manufacturing process:
Fired products: Refractory materials made by high temperature firing, such as sintered bricks, ceramic fibers, etc.
Unfired products: Refractory materials that do not need to be fired, such as chemically bonded refractory bricks, low cement castables, etc.
Cast products: Casting after melting the raw materials, such as cast alumina bricks.
5. Other special classifications:
Insulating refractory materials: materials with low thermal conductivity, such as diatomite bricks, lightweight clay bricks, etc., are mainly used for thermal insulation.
Anti-slag refractory materials: materials with strong resistance to slag erosion, such as magnesia-chrome bricks, etc.
These classification methods can be selected according to actual application needs in order to find the most suitable refractory materials.
