Sillimanite Brick

Sillimanite bricks are refractory bricks made from sillimanite-group minerals.  They are high-alumina refractory materials manufactured using natural sillimanite minerals as the main raw material, combined with appropriate amounts of clay, bauxite, and other binders, through processes of batching, molding, and high-temperature sintering. The products possess characteristics such as high load-bearing capacity at high temperatures, low porosity, good thermal shock resistance, and good wear resistance.

一.Characteristics of Sillimanite Brick

1)High Temperature Resistance: Refractory temperature of 1770-1830℃, load softening temperature of 1500-1650℃, does not melt or soften at high temperatures, suitable for extreme working conditions;

2)Crack Resistance and Dimensional Stability: Linear expansion rate at 1200℃ is only 0.5%-0.7%, strong resistance to thermal stress, reducing cracks and spalling;

3)Thermal Shock Resistance: Small mullitization volume effect, decomposition expansion offsets high-temperature shrinkage, ensuring structural stability under temperature fluctuations;

Corrosion Resistance: Excellent chemical stability, resistant to molten slag and glass liquid corrosion, wear-resistant and erosion-resistant, with low wear rate;

4）High Strength and Low Creep: Mullite crystal network supports high-temperature strength, not easily deformed under long-term load, ensuring equipment precision.

二．Physical And Chemical Indicators of Sillimanite Brick

三.Application of Sillimanite Brick

1). Metallurgical Industry

As a key refractory lining material for high-temperature metallurgical equipment, sillimanite bricks, with their strong high-temperature resistance, resistance to slag corrosion, and low creep, are widely used in: Blast furnaces: in areas such as the furnace lining, hearth, and bosh, to resist the erosion of molten iron and slag and high-temperature mechanical abrasion, maintaining the structural stability of the furnace;

Hot blast furnace: Checker bricks and combustion chamber lining, suitable for long-term high-temperature conditions above 1200℃, ensuring stable hot air temperature and improving thermal efficiency;

2)Converter/Electric arc furnace: Refractory bricks for the furnace mouth and tapping spout, withstanding the erosion of molten steel flow and sudden temperature changes, reducing the risk of damage and steel leakage;

Continuous casting machine: Refractory lining materials around the mold, resisting molten steel erosion and thermal shock from alternating heating and cooling, ensuring the continuity of the continuous casting process.

3). Glass Industry Applications:  Due to the high temperature and highly corrosive nature of molten glass, sillimanite bricks are the core refractory material for glass furnaces:

Glass tank furnaces: Used in critical areas such as the flow channel, charging port, refining zone, and tank walls, providing resistance to corrosion and penetration by molten glass, reducing glass contamination, and withstanding thermal shock from frequent temperature changes;

Glass fiber furnaces: Used as the lining of the melting tank, meeting the high-temperature melting requirements of glass fiber production, ensuring long-term stable operation of the furnace, and reducing maintenance frequency.

4). Building Materials and Ceramics Industry: Meeting the requirements of high-temperature firing and structural stability in kilns: Ceramic roller kilns and tunnel kilns:  Lining bricks and burner bricks in the firing zone, withstanding temperatures above 1500℃ and material abrasion, maintaining uniform temperature distribution within the kiln; Cement rotary kilns: Transition zone and decomposition furnace lining, resisting erosion and wear from cement clinker and high-temperature gas flow, extending the service life of the kiln body.

5). Other Industrial Fields:Petrochemical industry: Cracking furnace and conversion furnace linings, suitable for high-temperature catalytic reaction conditions, resistant to media corrosion and high-temperature creep;

Waste incinerators: Furnace lining bricks, resisting high-temperature corrosion and fly ash erosion from incineration flue gas, ensuring the long-term stable operation of the incinerator;

Heat treatment furnaces: High-temperature furnace linings and furnace bottom support bricks, withstanding long-term high temperatures and temperature fluctuations, maintaining the structural precision of the furnace.