The Difference Between Alkali-Resistant Castables And High-Aluminum Castables

There are significant differences between alkali-resistant castables and high-aluminum castables in many aspects. These differences are mainly reflected in composition, performance, use, and structural characteristics.

1. Differences in ingredients

Alkali-resistant castable: The main components are MgO, MgO-Al₂O₃, MgO-CaO, MgO-CaO-SiO₂, etc. These ingredients give the alkali-resistant castable excellent alkaline corrosion resistance.
High aluminum castable: The main component is Al₂O₃, and the high alumina content makes it perform well in high-temperature environments.

2. Performance characteristics

Alkali-resistant castable: It has high strength, alkali resistance, and excellent corrosion resistance. It can withstand the erosion of various slag materials, such as slurry, molten slag, limestone, etc., without causing erosion. At the same time, alkali-resistant castables also have good alkali-resistant aggregate reaction properties, thermal shock stability, wear resistance, and air permeability.
High-aluminum castables: famous for their excellent high-temperature resistance, thermal shock resistance, chemical erosion resistance, and load resistance. At high temperatures, high-aluminum castables will not expand, crack or soften, and can withstand changes such as alternating hot and cold, rapid heating, and rapid cooling. In addition, its structure is dense, able to withstand various loads and vibrations, and is not prone to problems such as cracks and collapse.

3. Different uses

Alkali-resistant castables: widely used in high-temperature reaction equipment linings in metallurgy, glass, chemical, and other industries and hot workpieces in glass kilns and other equipment. It is also an excellent furnace lining material used to manufacture different furnaces and furnace linings.
High-aluminum castables: are mainly used in a wide range of fields such as high-temperature furnace fire surfaces, molten metal linings, metallurgical reactors, furnace expansion, and economical kilns.

4. Structural features

Alkali-resistant castable: Its structure can be divided into three types: microcrystalline, mica, and crystalline. These structural characteristics help it resist alkaline erosion and high-temperature wear.
High-aluminum castables: can be divided into those with high mass density and coarse-grained structure and those with low mass density but with fine-grained structure. This structural feature enables high-aluminum castables to maintain stability and strength at high temperatures.

In summary, there are obvious differences between alkali-resistant castables and high-aluminum castables in terms of composition, performance, use, and structural characteristics. The choice of castable should be comprehensively considered based on the specific use areas and actual needs.