What are the Main Components of Silicon Mullite Bricks?

The main components of silicon mullite brick include aluminum silicate (Al2Si2O7) and silicon dioxide (SiO2).

Silicon mullite bricks are refractory bricks made of special high-alumina bauxite clinker, andalusite, silicon carbide, and homogenized bauxite as the main raw materials, which are formed by high pressure molding and fired at high temperatures.

The “silicon” in silicon mullite bricks refers to silicon carbide, and “Mo” refers to mullite. In fact, silicon mullite bricks are refractory bricks made of high alumina bauxite and silicon carbide as the main raw materials through sintering. Essentially, silicon mullite bricks are just high alumina bricks with silicon carbide added.

Silicon mullite bricks are a refractory material usually made of a mixture of aluminum silicate and silica. These two components play an important role in bricks:

Aluminum silicate (Al2Si2O7): also known as mullite (Mullite), is one of the main crystal phases of silica-molybdenum bricks. It has good fire resistance and thermal stability and can withstand thermal expansion and thermal shock under high-temperature conditions.

Silicon dioxide (SiO2): also known as quartz, is another important ingredient in silicon mullite bricks. It has a high melting point and excellent high-temperature resistance, which helps to improve the refractory performance and thermal stability of silicon mullite bricks.

The formulation of silicon mullite bricks may also include other auxiliary ingredients, such as clay, graphite, etc., which can be adjusted according to specific applications and needs.

Silicon mullite bricks are characterized by high strength, wear resistance, and good seismic stability. It has achieved good results in the use of rotary kilns. The service life of the firing zone and transition zone of the cement rotary kiln is better than that of spinel bricks. The main reason is It is the spinel brick that forms an erosion zone due to alkali erosion during use, causing cracks and peeling on the hot surface to accelerate damage. Silicon mullite bricks have a dense structure, mullite, and SiC crystals are stable, and a continuous SiO2 dense layer is formed on the brick surface, which prevents the erosion of gases and melts. And SiC has high thermal conductivity, a small thermal expansion coefficient, and good thermal shock resistance of products. These performance characteristics make the silicon mullite bricks not easy to break and peel off, and because the thermal conductivity is lower than that of magnesia materials, the cylinder will not be overheated, which not only ensures the normal operation of the rotary kiln cylinder but also saves fuel.

Due to its excellent fire resistance and thermal stability, silicon mullite bricks are widely used in high-temperature industrial fields, such as rotary kilns, glass kilns, metallurgical furnaces, petrochemical equipment, etc.