White corundum is widely used in refractories, mainly in the following aspects:

I. Manufacture of refractory bricks

White corundum is an important raw material for manufacturing high-performance refractory bricks such as high-alumina bricks and mullite brick. Its high-purity alumina (Al₂O₃ content ≥99%) endows refractory bricks with extremely high fire resistance (up to more than 1800°C), and at the same time, it has good thermal shock resistance and chemical corrosion resistance. The addition of white corundum can significantly improve the hardness and wear resistance of refractory bricks and make them more stable in high temperature environment.

II. Refractory castable

White corundum is used to manufacture high alumina castable and mullite castable. These castables have excellent high temperature resistance, thermal shock resistance and chemical erosion resistance, and are suitable for lining and repairing of various high temperature furnaces. For example, white corundum is one of the main raw materials in large ladle castable and high-grade iron channel castable.

III. Refractory fibers

White corundum can be used to make refractory fibers, such as alumina fibers and mullite fibers. These fiber materials have the characteristics of light weight, high temperature resistance and thermal shock resistance, and are suitable for high temperature heat insulation and heat preservation.

IV. Refractory coatings

White corundum fine powder can be used to make refractory coatings, which have excellent high temperature resistance and chemical corrosion resistance, and can protect metal and nonmetal materials from high temperature and corrosion.

V. Other refractory products

White corundum can also be used to manufacture refractory components such as various high-temperature containers, pipelines, furnace linings, furnace tops and furnace doors. In addition, white corundum micropowder can be used to manufacture special refractories such as high-temperature ceramics and cathode insulators of electron tubes.

Performance improvement of white corundum in refractories

High temperature stability: The melting point of white corundum is as high as 2050°C, and it can remain stable for a long time in high temperature environment.

Corrosion resistance: white corundum has high corrosion resistance to corrosive substances such as acid and alkali.

Wear resistance: The high hardness of white corundum (Mohs hardness is 9) makes it hard to wear under high temperature and mechanical impact.

Thermal shock resistance: the thermal expansion coefficient of white corundum is low, and it can withstand the sharp change of temperature.

White corundum has been widely used in high-temperature industrial fields such as steel, glass, cement and ceramics because of its excellent properties.