Materials and properties of different high alumina bricks

November 05, 2018

Materials and properties of different high alumina bricks

1.Ordinary high alumina bricks

The main mineral composition of the refractory brick is mullite, corundum and glass phase. As the content of Al2O3 in the product increases, the content of mullite and corundum also increases, the glass phase will decrease accordingly, and the refractoriness and high temperature performance of the product will follow improve. Ordinary high alumina bricks have a series of better refractory properties than clay bricks. It is a kind of material with good application effect and wide application, and is widely used in various thermal kilns and furnaces. Compared with clay bricks, it can effectively improve the service life of the furnace.

2.Low creep high alumina bricks

Improve the creep resistance of high alumina bricks by using a so-called unbalanced reaction. According to the use temperature of the kiln, adding three stone minerals, activating alumina, etc. to the matrix, the composition of the matrix is close to or completely composed of mullite. Because the mullite of the matrix will increase the mullite content of the materials and reduce the content of glass phase. The excellent mechanical and thermal properties of mullite are beneficial to the improvement of the high temperature performance of the material. Low creep high aluminum bricks are widely used in thermal furnaces such as hot blast stoves and blast furnaces.

3.High refractoriness under load high alumina bricks

Compared with ordinary high alumina bricks, the high refractoriness under load high-alumina bricks differ in the matrix part and the binder part: besides adding three stone minerals, according to the theory of chemical composition close to mullite after burning, high alumina materials, such as corundum powder, high alumina corundum powder, etc. are reasonably introduced; binders are selected for high quality ball clay, etc., depending on the variety, different clay composite binders, or mullite binders. Through the above method, the load softening temperature of the high alumina bricks can be increased by about 50--70℃.