High Alumina Brick

High alumina brick is a neutral refractory material. It not only has certain corrosion resistance to acidic and alkaline slag, but also features high cold-pressing strength, strong erosion resistance, strong impermeability and high refractoriness under load.
High alumina brick is a refractory material mainly composed of Al₂O₃. It is classified as an aluminosilicate refractory product with an alumina (Al₂O₃) content exceeding 48%, demonstrating nearly neutral properties and being resistant to erosion by both acidic and alkaline slags. However, due to the presence of SiO₂, its resistance to alkali residue is relatively weak. It is made from bauxite or other high-alumina raw materials through molding and calcination, featuring high thermal stability and a refractoriness of over 1770°C.

High alumina bricks are mainly used as linings for high-temperature kilns such as blast furnaces, hot blast stoves, top plates of electric furnaces, reverberatory furnaces, and rotary kilns. They can also be used as regenerative square bricks for open-hearth furnaces, stoppers and nozzle bricks for gating systems.

Item	Specification
	LZ-80	LZ-75	LZ-70	LZ-65	LZ-55	LZ-48
Al2O3  %	≥80	≥75	≥70	≥65	≥55	≥48
Apparent Porosity, %	≤21	≤24	≤24	≤24	≤22	≤22
CCS, MPa	≥70	≥60	≥55	≥50	≥45	≥40
0.2MPa RUL ℃	≥1530	≥1520	≥1510	≥1500	≥1450	≥1420
PLC, %	1500℃×2h-0.4~0.2		1450℃×2h-0.4~0.1

1. Metallurgical industry
   Electric arc furnace (EAF) : It is applied to the furnace cover and furnace wall to resist high-temperature electric arcs and slag erosion.
   Blast furnace
   Furnace body: Resistant to mechanical wear and gas erosion.
   Furnace bottom: Capable of withstanding the penetration and erosion of molten iron.
   Hot blast stove: Used for arches and walls, it withstands thermal cycling and high-temperature gas flow, ensuring stable performance.
2. Building materials industry
   Cement kiln: Installed in the transition zone and firing zone, it can resist high temperatures and alkaline erosion.
   Glass furnace: Used for pool walls and combustion chambers to resist molten glass and flame radiation.
3. Power industry
   In thermal power generation boilers, they are used as linings for furnaces and flues to resist high-temperature gases and wear. Because of their resistance to corrosive gases, they are also used in waste incineration plants.
4. Chemical industry
   Gasifiers and ammonia conversion furnaces used in high-temperature reaction zones provide structural integrity and insulation.
5. Other applications
   Due to its high-temperature stability and wear resistance, it is also used as a square brick in open-hearth furnaces, pouring plugs and nozzle bricks.