Alumina (corundum) industrial Ceramic sleeves are high-performance ceramic components made primarily from alumina and are widely used in industry.

Performance

High Hardness and Wear Resistance: Made primarily of 99.9% pure α-alumina, they undergo high-temperature sintering to form a dense structure with a Mohs hardness of 9, second only to diamond. They offer excellent wear resistance and effectively resist erosion and wear from materials.

High-Temperature Resistance: They can withstand continuous temperatures of 1600°C and short-term thermal shocks of 1800°C, significantly higher than metal pipes. They maintain stable structure and performance in high-temperature industrial environments.

Excellent Corrosion Resistance: With the exception of hydrofluoric acid, they are resistant to 99% of acids and alkalis, molten metals, and halogen gases, enabling long-term use in highly corrosive environments. Thermal Stability and Thermal Shock Resistance: Some corundum Ceramic Tubes can maintain structural integrity even under ultra-high-speed thermal shock of 2000°C/s, demonstrating excellent thermal shock resistance and the ability to withstand thermal shock and chemical corrosion at high temperatures.

Electrical Insulation: Alumina ceramics offer excellent electrical insulation, with a volume resistivity of up to 10¹⁴Ω・cm, making them suitable for industrial applications requiring insulation.

Specifications: Taking high-purity alumina thermocouple protection tubes as an example, their density is typically 3.88g/cm³, purity can reach 99.5%, Mohs hardness is 9, and the maximum long-term operating temperature is 1700°C. Outer diameters range from 4 to 120mm, and lengths range from 0 to 2500mm.

Applications

Semiconductor Industry: As a core carrier in diffusion furnaces, it withstands corrosion in hydrogen atmospheres at 1300°C, reducing contamination rates to below 0.1ppm. Major manufacturers such as TSMC and SMIC have adopted it, helping to improve chip yields. New Energy Industry: Can be used in the production of positive and negative electrode materials for lithium batteries. For example, as protective tubes in high-temperature furnaces, silicon nitride-coated corundum tubes can extend their lifespan to over two years, enhancing the purity of the positive electrode material.

Metallurgical Industry: Can be used to protect fire tubes in metallurgical furnaces. Corundum composite tubes (Al₂O₃-ZrO₂) can withstand corrosion from molten titanium at 1700°C and have a lifespan exceeding 300 heats, improving metallurgical production efficiency and equipment lifespan.

Power Industry: Can be used as thermocouple protection tubes, isolating temperature measuring elements from the outside world, protecting them from contamination, oxidation, and physical damage in various gas environments, ensuring the normal operation of power equipment and accurate temperature monitoring.