Alumina Bubble Brick
New-Type Ultra-High Temperature Energy-Saving Thermal Insulation Material
Application
Working layer in direct contact with flames can also serve as insulation layer, suitable for kilns with hydrogen and reducing atmospheres.
Description
Alumina Bubble Brick is an insulating refractory product primarily made from alumina hollow spheres. The manufacturing process involves: proportioning alumina hollow spheres, sintered alumina fine powder, and binders in specific ratios, followed by shaping, drying, and firing. Due to its brick morphology and loosely porous structure (closed pores), it is also referred to as foamed alumina brick. Its crystalline structure consists of α-Al2O3 microcrystals, and various shapes of products can be fabricated based on alumina hollow spheres. This product exhibits extremely high mechanical strength, several times that of conventional lightweight materials, while its bulk density is only half that of corundum products. Alumina hollow sphere bricks are also known as corundum hollow sphere bricks.
Specifications
| Item |
Alumina Bubble Brick |
ZrO2 Bubble Brick |
Sialon bonded |
|
|---|---|---|---|---|
|
LKZ-88 |
LKZ-98 |
ZKZ-98 |
LKZ-70 |
|
|
Service Temperature °С |
1650 |
1800 |
2000～2200 |
1600 |
|
Al2O3 % ≥ |
88 |
99 |
– |
70 |
|
ZrO2 % ≥ |
– |
– |
98 |
– |
|
SiO2 % ≤ |
– |
0.2 |
0.2 |
– |
|
Fe2O3 % ≤ |
0.3 |
0.15 |
0.2 |
N≥5 |
|
Bulk Density g/cm3 |
1.30～1.45 |
1.40～1.65 |
≤ 3.0 |
≤ 1.5 |
|
Cold Crushing Strength MPa ≥ |
10 |
9 |
8 |
15 |
|
Refractoriness Under Load 0,2 MPa T0.6 °С ≥ |
1650 |
1700 |
1700 |
1700 |
|
Thermal Expansion Rate ×10-6 1600°С×3h % |
±0.3 |
±0.3 |
±0.2 |
– |
|
Linear Change on Reheating ×10-6 (RT~1300°С) |
~8.0 |
~8.6 |
– |
– |
|
Thermal Shock Resistance 1100°С – water cooling, cycle |
– |
– |
– |
15 |
|
Thermal Conductivity 800°С W/(m·K) ≤ |
0.9 |
1.0 |
0.5 |
1.1 |
| Service Area |
|
|
|
|
Ultra-light Alumina Bubble Brick
| Item | SLKZ-99 |
|---|---|
| Al2O3 % ≥ | 99 |
| Bulk Density g/cm3 ≤ | 0.85 |
| Cold Crushing Strength MPa ≥ | 3 |
| Thermal Conductivity 400°С W/(m·K) ≤ | 0.26 |
| Linear Change on Reheating 1500°С×6h % ≤ | 1.0 |
Features
Ultra-High Service Temperature
Maintains stability at temperatures exceeding 1750°C. Exhibits minimal linear dimensional change after reburning, resists corrosion from hydrogen fluoride and other gases, significantly extending service life.Structural Optimization
Traditional high-temperature materials are typically heavy bricks (bulk density 2.6-3.0 g/cm³), while alumina hollow sphere bricks have a density of only 1.1-1.5 g/cm³. Each cubic meter of volume reduces mass by 1.1-1.9 tons.Material Savings
When achieving the same temperature parameters: The cost of heavy bricks is comparable to hollow sphere bricks; No additional insulating refractory layer is required; Saves 1.1-1.9 tons of material per cubic meter; Reduces the consumption of insulating refractories by 80%.Energy Savings
Alumina hollow spheres possess remarkable thermal insulation properties. Their low thermal conductivity provides effective thermal protection, reduces heat loss, improves thermal efficiency, and achieves energy savings of over 30%.Applications
Wide Application Range
- Hot Face Lining for Kiln Working Surfaces: Suitable for direct flame contact environments due to exceptional thermomechanical properties.
- Thermal Insulation Material for Various Industrial Kilns: Ideal for applications without contact with molten materials or corrosive gas atmospheres.
Main Application Areas:
- Gasifiers
- Carbon Black Reactors
- Induction Electric Furnaces
- Downdraft Kilns
- Shuttle Kilns
- Molybdenum Wire Resistance Furnaces
- Tungsten Rod Furnaces
- Induction Melting Furnaces
- Nitriding Furnaces