Description
Magnesia-alumina brick is a type of alkaline refractory material made from magnesite and industrial lead oxide or bauxite as raw materials. These materials are crushed, shaped, and then sintered at around 1600°C. The refractoriness of magnesia-alumina bricks is greater than 2000°C and they exhibit better resistance to thermal shock compared to magnesia bricks. Additionally, they are capable of withstanding corrosion from alkaline slag.
Magnesia-alumina spinel bricks are refractory materials primarily composed of magnesite (MgO) and bauxite (Al2O3), which form the spinel phase (MgAl2O4)through sintering. Spinel is a mineral with a high melting point, excellent thermal stability, and corrosion resistance. The adding of spinel enhances the overall performance of the bricks, especially high-temperature resistance, corrosion resistance and thermal shock resistance.
Specification
| Item | Grade | |||
| MA—90 | MA—85 | MA—80 | MA—75 | |
| ω(MgO)/%≥ | 90 | 85 | 80 | 75 |
| ω(Al₂O₃)/% | 3～8 | 5～12 | 8～17 | 8～12 |
| Apparent Porosity/%≤ | 17 | 17 | 16 | 19 |
| Bulk density/(g/cm³)≥ | 2.90 | 2.95 | 2.95 | 2.85 |
| Cold Crushing Strength/MPa≥ | 45 | 45 | 55 | 40 |
| 40 | 40 | 50 | 35 | |
| Refractoriness Under Load / 0.2 MPa T0.6/℃≥ | 1700 | 1700 | 1700 | 1650 |
| Thermal Shock Resistance(1100℃~cold)≥ | 3 | 8 | 12 | 8 |
Applications
Widely used as linings and upper cones and other key parts of steel-making converters, electric furnaces, refining furnaces.
Used as linings in the smelting furnaces of non-ferrous metals such as copper, nickel, lead, and zinc.
Used in the cement rotary kilns, lime kilns and ceramic kilns.
