Bubble Alumina
Bubble alumina is a new type of high-temperature insulation material, consisting of a-Al2O3 microcrystals. Various shaped products can be made with bubble alumina as the main material, with a maximum usage temperature of 1800°C. These products have high mechanical strength, several times that of general lightweight products, yet only half the bulk density of corundum products.
Bulk Density
| Size | 5-4mm | 4-3mm | 3-2mm | 2-1mm | 1-0.5mm | 3-0.2mm | 0.5-0.2mm |
| g/cm3 | 0.45 | 0.55 | 0.65 | 0.75 | 0.85 | 0.85 | 0.95 |
Features
- High porosity: bubble alumina has low density and high porosity, making it an ideal material for various applications.
- High-temperature resistance: it exhibits good stability and oxidation resistance at high temperatures, capable of withstanding temperatures up to 1750°c.
- Chemical stability: with high chemical stability, bubble alumina is resistant to chemical corrosion and corrosive gases, making it suitable for applications involving chemicals and hazardous substances.
- Good mechanical properties: bubble alumina has high strength and rigidity, maintaining its shape and structural integrity under pressure.
- Variety of sizes and shapes: it can be prepared in various sizes and shapes, including spherical, oval, and irregular shapes, to meet different application needs.
Applications
Bubble alumina can be used as high-temperature and ultra-high-temperature insulation filler, lightweight aggregate for high-temperature refractory concrete, and high-temperature castable. Bubble alumina refractory bricks are suitable for high-temperature energy-saving applications (more than 30%) such as downdraft kilns, shuttle kilns, molybdenum wire furnaces, tungsten rod furnaces, induction furnaces, and nitriding furnaces. They help reduce furnace weight, improve structure, save materials, and conserve energy, achieving significant results.
Typical Chemical Analysis/Physical Properties
| Chemical Index | |||||||||
| Size | Al2O3 | Fe2O3 | SiO2 | Na2O | MgO | K2O | Cao | ||
| 0.2-5mm | ≥99% | ≤0.15% | ≤0.3% | ≤0.5% | ≤0.1% | ≤0.1% | ≤0.1% | ||
| Physical Index | |||||||||
| Bulk Density | Refractory Temperature | Appearance | |||||||
| 0.45-0.95g/cm3 | 1800°C | White hollow spheres | |||||||
Production Flow
- Melt industrial alumina with over 98% content in a three-phase electric arc furnace.
- Use compressed air to blow the molten alumina into small hollow spheres.
- Select good spheres, ensuring a breakage rate within 10%.
- Screen different models.
- Package and store in the warehouse.
- Select good spheres
- Screen different models
- Package and store
