High Alumina Brick - High alumina brick

High alumina brick is a type of refractory material, and its main component is Al2O3.

If the Al2O3 content is higher than 90%, it is called corundum brick. Due to different resources, the standards of various countries are not completely consistent. For example, European countries have set a minimum Al2O3 content of 42% for high alumina refractory materials. In China, the Al2O3 content in high alumina bricks is usually divided into three grades: Grade I - Al2O3 content>75%; Grade II - Al2O3 content of 60-75%; Grade III - Al2O3 content of 48-60%

Aluminum silicate refractory products with a content of Al2O3 higher than 48%.

A neutral refractory material with an alumina content of over 48%. Made from raw materials with high alumina content, such as bauxite, through molding and calcination. High thermal stability, with a fire resistance of over 1770 ℃. Good slag resistance, used for lining steel furnaces, glass melting furnaces, cement rotary furnaces, etc.

High alumina brick mainly used for lining blast furnaces, hot blast stoves, electric furnace tops, blast furnaces, reverberatory furnaces, and rotary kilns. In addition, high alumina bricks are widely used as regenerative grid bricks for open hearth furnaces, plugs for pouring systems, and spout bricks. But the price of high alumina bricks is higher than that of clay bricks, so there is no need to use high alumina bricks where clay bricks can meet the requirements.

Characteristic

a, refractoriness

The fire resistance of high alumina bricks is higher than that of clay bricks and semi silica bricks, reaching 1750-1790 ℃, and belongs to advanced refractory materials.

b, refractoriness under load

Due to the high Al2O3 content and low impurity content in high alumina products, which results in less formation of easily melted glass bodies, the load softening temperature is higher than that of clay bricks. However, since mullite crystals do not form a network structure, the load softening temperature is still not as high as that of silica bricks.

c, slag resistance

High alumina bricks contain more Al2O3, which is close to neutral refractory materials and can resist the erosion of acidic and alkaline slag. Due to the presence of SiO2, the ability to resist alkaline slag is weaker than that of acid resistant slag.

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