Brief Introduction
High alumina brick is a kind of alumina-silicate refractory material with content of alumina oxide more than 48%. It is calcined and formed by the raw material of banxite or the material with high content of AL2O3. High thermal stability, the refractoriness is more than 1770℃.
Technical Datas
| High Alumina Refractory Brick Physical and Chemical Index: | ||||||
| Item | Properties | |||||
| A-80 | A-75 | A-65 | A-55 | A-48 | ||
| Al2O3 (%) | 80 | ≥75 | ≥65 | ≥55 | ≥48 | |
| Refractoriness (℃ ) | ≥1790 | ≥1790 | ≥1790 | ≥1770 | ≥1750 | |
| Bulk density (g/cm3) | 2.65 | 2.5 | 2.45 | 2.4 | 2.3 | |
| Softening temperature under load (°C ) | 1530 | ≥1520 | ≥1500 | ≥1470 | ≥1420 | |
| Reheating Linear changes Rate (%) | 1500°CX2H | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 |
| 1450°CX2H | -0.4 | -0.4 | -0.4 | -0.4 | -0.4 | |
| Apparent porosity (%) | 22 | ≤23 | ≤23 | ≤22 | ≤22 | |
| Cold crushing strength (Mpa) | 55 | ≥50 | ≥45 | ≥40 | ≥35 | |
| Application | steel furnace, glass furnace, sodium silicate furnace, ceramic shuttle kiln, cement rotary kiln, blast furnace, electric furnace, blast furnace and reverberatory furnace. | |||||
Features
a. Refractoriness
The refractoriness of high-alumina bricks is higher than that of clay bricks and semi-silica bricks, reaching 1750~1790°C, which is a high-grade refractory material.
b. Load softening temperature
Because the Al2O3 in high alumina products is high, the amount of impurities is small, and the formation of fusible glass is less, the softening temperature under load is higher than that of clay bricks, but because the mullite crystallization does not form a network structure, the softening temperature under load is still not as high as that of silica bricks.
c. Slag resistance
There are more Al2O3 in high alumina bricks, which are close to neutral refractory materials, and can resist the erosion of acid slag and alkaline slag. Because it contains SiO2, the ability to resist alkaline slag is weaker than that of acid slag.
Application
High alumina brick is widely used for blast furnaces, hot blast stove,steel ladle lining, reheating furnace, cement kiln, tunnel kiln,boiler, coke oven, carbon furnace, glass kiln , steel smelting furnace and various kiln lining and thermotechnical equipment, etc.
