+86-15527482889
High-Quality Silicon Mullite Bricks for Cement Industry from China Suppliers and Factory
Excellent High-Temperature Performance
The refractoriness is above 1790℃, and the starting temperature of load softening under 0.2MPa is up to 1650℃, which can withstand the high-temperature environment of industrial kilns for a long time without deformation or damage. It is especially suitable for the transition zone and decomposition zone of cement kilns with frequent temperature fluctuations.
Superior Wear & Erosion Resistance
The main crystal phases are corundum, silicon carbide and mullite with high hardness (Mohs hardness up to 9.5), and the product structure is dense. The room-temperature wear resistance is ≤7.8 cm², which can effectively resist the friction and erosion of high-temperature materials and corrosive gases, reducing the loss of kiln linings.
Outstanding Thermal Shock Stability
Thanks to the low thermal expansion coefficient of silicon carbide, the silicon mullite brick has excellent thermal shock resistance. After 15 times of water cooling tests at 1000℃, it still remains intact without cracking or spalling, adapting to the rapid temperature changes in kilns.
Good Thermal Insulation Effect
The thermal conductivity at 1000℃ is ≤1.7 W/(m·k), which is lower than that of alkaline products. It can effectively reduce the surface temperature of the kiln cylinder (lower by more than 50℃ compared with magnesia-aluminum spinel bricks), reduce energy loss and protect the kiln cylinder.
| Item | Silica Mullite Brick | ||
|---|---|---|---|
| SM-1650 | SM-1680 | SM-1680T | |
| Al₂O₃ % | ≥65 | ≥65 | ≥68 |
| SiO₂+SiC % | ≥30 | ≥30 | ≥30 |
| Apparent Porosity % | ≤20 | ≤18 | ≤17 |
| Bulk Density g/cm³ | ≥2.65 | ≥2.65 | ≥2.70 |
| Cold Crushing Strength MPa | ≥95 | ≥90 | ≥90 |
| Refractoriness Under Load ℃ (0.2MPa, 0.6%) | ≥1650 | ≥1680 | ≥1680 |
| Thermal Shock Stability (1100℃ cooling) times | ≥10 | ≥12 | ≥15 |
| Thermal Conductivity (1000℃) W/(m·k) | ≤2.3 | ≤2.0 | ≤1.7 |
As the largest application field of silicon mullite brick, it accounts for more than 38% of the global demand. It is mainly used in key parts of new dry process cement kilns, including the transition zone, decomposition zone, cooling machine and kiln mouth. The transition zone of cement kilns has no kiln skin protection, and is subjected to high temperature (up to 1400℃), material friction and alkaline erosion. Silicon mullite brick can form a continuous SiO₂ dense layer on the surface, which effectively prevents the penetration of molten substances and has excellent corrosion resistance.
It is widely used in ironmaking, steelmaking and non-ferrous metal smelting fields, accounting for about 28% of the market demand. In electric arc furnaces, converter linings, ladles and other equipment, silicon mullite brick can withstand high temperature and strong corrosion of molten metal and slag. Especially with the increase of electric furnace steelmaking ratio, the demand for high-wear and long-life refractory materials is increasing. The high hardness and wear resistance of silicon mullite brick can effectively resist the scouring of molten steel and slag, and its good thermal shock stability can adapt to the rapid temperature rise and fall during smelting, ensuring the safe and stable operation of smelting equipment.
Lime production process will generate high temperature and strong alkaline substances, which have strong corrosion to kiln linings. Silicon mullite brick has excellent alkali corrosion resistance and thermal shock stability, which can maintain the integrity of the kiln lining structure in the harsh environment of lime kilns. It is mainly used as the inner lining of lime kilns, which can reduce the cracking and spalling of the lining caused by temperature changes and chemical corrosion, and extend the service life of the lime kiln. It is suitable for various types of lime kilns such as shaft kilns and rotary kilns.
With the development of new environmental protection power generation methods such as waste incineration and biomass power generation, the furnace environment is more complex and harsh, which provides a new market for silicon mullite brick. It is used in the furnace linings of waste incinerators, biomass boilers and thermal power plant boilers. It can resist the corrosion of harmful gases and high-temperature ash generated during combustion, and has good wear resistance and thermal shock stability. It can ensure the long-term stable operation of power generation equipment and reduce the maintenance cost of power plants.
Silicon mullite brick is a high-performance refractory material whose main crystal phases include corundum, silicon carbide (SiC) and mullite. These components work together to provide exceptional high-temperature resistance, wear resistance, and thermal shock stability, making it ideal for demanding industrial kiln applications.
Silicon mullite brick has a refractoriness above 1790℃. Under a load of 0.2MPa, the starting temperature of load softening can reach up to 1650℃ (SM-1650 grade) or 1680℃ (SM-1680 / SM-1680T grades), ensuring reliable long-term performance in extreme high-temperature industrial environments.
Compared to magnesia-aluminum spinel bricks, silicon mullite brick offers lower thermal conductivity (≤1.7 W/(m·k) at 1000℃), which reduces the kiln cylinder surface temperature by more than 50℃. It also provides superior wear resistance, excellent alkali corrosion resistance, and outstanding thermal shock stability — all critical requirements for the transition and decomposition zones of cement kilns.
Silicon mullite brick demonstrates outstanding thermal shock stability. The SM-1680T grade can withstand at least 15 water-cooling cycles from 1100℃ without cracking or spalling. This is achieved thanks to the low thermal expansion coefficient of silicon carbide, allowing the brick to adapt to rapid and frequent temperature fluctuations inside industrial kilns.
Silicon mullite brick is widely applied across multiple industries including: the cement industry (transition zones, decomposition zones, kiln mouths), the metallurgical industry (electric arc furnaces, converter linings, ladles), the lime kiln industry (shaft kilns and rotary kilns), and the power industry (waste incinerators, biomass boilers, and thermal power plant boilers).
The three grades differ primarily in density, porosity, thermal shock resistance and thermal conductivity. SM-1680T offers the highest performance: Al₂O₃ content ≥68%, apparent porosity ≤17%, bulk density ≥2.70 g/cm³, thermal shock stability ≥15 times, and the lowest thermal conductivity of ≤1.7 W/(m·k) at 1000℃. SM-1650 is a cost-effective option for less demanding conditions, while SM-1680 provides a balanced performance between the two.



