Silicon carbide bricks are refractory products primarily composed of silicon carbide, typically with a silicon carbide content of 80–85%. The main raw material is black silicon carbide (with an SiC content exceeding 96%); binders are sometimes added, and the bricks are produced through processes such as batching, mixing, forming, and firing. Major varieties include oxide-bonded, carbon-bonded, silicon nitride-bonded, self-bonded, and recrystallized silicon carbide bricks, as well as semi-silicon carbide bricks.
Characteristics of Silicon Carbide Bricks
- High thermal conductivity: Silicon carbide bricks possess high thermal conductivity, allowing for rapid heat transfer.
- High wear resistance: They exhibit excellent wear resistance and can withstand significant mechanical stress.
- Thermal shock resistance: Silicon carbide bricks remain stable even in environments with drastic temperature fluctuations.
- Erosion resistance: They offer excellent resistance to erosion by various chemical substances.
Application Areas
- Non-ferrous metal smelting: Used in industries such as non-ferrous metal smelting; applications include ceramic, enamel, and cement rotary kiln openings, as well as glass annealing furnaces and various high-temperature furnaces.
- Blast furnace linings: Used for blast furnace linings, aluminum electrolytic cell linings, glass melting tanks, structural ceramics, sanitary ware, and household ceramics.
- Industrial ceramics: Used for load-bearing plates, burner backplates, pusher plates, material troughs, and hearth plates for annealing furnaces; also used as linings for waste incinerators, electric heat-treatment furnaces, and soaking pits.
- High-tech ceramics: Used for aluminum electrolytic cell linings, molten aluminum conduits, kiln furniture for ceramic kilns, the lower shaft, waist, and bosh sections of large and medium-sized blast furnaces, aluminum refining furnace linings, zinc distillation retort linings, etc.
- Chemical industry: Used in oil-gas generators and organic waste incinerators.
- Silicate industry: Used for shelf plates and flame-shielding materials in silicate industry kilns.
Usage Precautions
- Moisture protection: Silicon carbide absorbs water; therefore, the bricks should be stored in a dry environment for several days prior to use to ensure they do not become damp.
- Dust protection: Silicon carbide is susceptible to dust and fine particles, which can damage its surface and performance. Therefore, contact with dust or other fine particles should be avoided during storage and use.
- Shock protection: Silicon carbide is a brittle material; impacts and vibrations should be avoided during transportation and use.
- Avoid prolonged contact with moisture and strong acids or alkalis: Although silicon carbide is resistant to acids and alkalis, prolonged exposure to moisture and strong acidic or alkaline substances can degrade its quality and impair its performance.