Description
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.
Advantages of Magnesia Alumina Spinel Brick
• Chrome-Free and Environmentally Friendly
Magnesia alumina spinel brick contains no chrome oxide and helps eliminate Cr6+ pollution risk, making it an environmentally friendly substitute for magnesia chrome brick.
• Low Porosity and High Strength
Low apparent porosity, high cold crushing strength and high modulus of rupture at high temperature help improve lining density and structural stability.
• Corrosion Resistance
The magnesia-alumina spinel structure provides good resistance to chemical corrosion, material erosion and high-temperature furnace atmosphere.
• Thermal Shock Stability
Good thermal shock stability helps reduce cracking, peeling and spalling caused by repeated heating and cooling, supporting longer lining service life.
Specification of Magnesia Alumina Spinel Brick
| 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 |
Standard Brick Sizes
VDZ Standard
| Brick Type | Size | Diameter | volume | |||
| a | b | h | l | D1) | ||
| mm | mm | mm | mm | mm | dm3 | |
| B322 | 76.5 | 66.5 | 220 | 198 | 3366 | 3.11 |
| B422 | 75.0 | 68.0 | 220 | 198 | 4714 | 3.11 |
| B622 | 74.0 | 69.0 | 220 | 198 | 6512 | 3.11 |
ISO Standard
| Brick Type | Size | Diameter | volume | |||
| a | b | h | l | D1) | ||
| mm | mm | mm | mm | mm | dm3 | |
| 320 | 103.0 | 89.0 | 200 | 198 | 3000 | 3.8 |
| 420 | 103.0 | 92.5 | 200 | 198 | 4000 | 3.87 |
| 620 | 103.0 | 96.2 | 200 | 198 | 6176 | 3.94 |
| 322 | 103.0 | 88.0 | 220 | 198 | 3080 | 4.16 |
| 422 | 103.0 | 91.5 | 220 | 198 | 4017 | 4.24 |
| 622 | 103.0 | 95.5 | 220 | 198 | 6160 | 4.32 |
| 425 | 103.0 | 90.0 | 250 | 198 | 4038 | 4.78 |
| 625 | 103.0 | 94.5 | 250 | 198 | 6176 | 4.89 |
| 825 | 103.0 | 96.5 | 250 | 198 | 8077 | 4.94 |
Product Size: We offer refractory brick sizes that comply with ISO, EN, ASTM, JIS, etc, and customized sizes.
Applications of Magnesia Alumina Spinel Bricks
Magnesia-alumina spinel bricks serve as an ideal substitute for magnesia chrome bricks due to their superior eco-friendliness. Magnesia-alumina spinel bricks are widely used for the linings and upper cones of steel-making converters, electric furnaces, and refining furnaces. They are also applied in non-ferrous smelting furnaces (copper, nickel, lead, and zinc), as well as in cement rotary, lime, and ceramic kilns.
Manufacturing and Quality Control
JHYRef controls magnesia alumina spinel brick quality from raw material selection to final inspection. High-quality magnesia and alumina spinel raw materials are selected according to product grade and application requirements. The materials are crushed, screened, mixed, shaped under pressure, dried, and fired at high temperature to form a stable magnesia-spinel structure with good bonding strength and volume stability.
Quality control can include chemical composition testing, dimension inspection, apparent porosity, bulk density, cold crushing strength, modulus of rupture at high temperature, refractoriness under load, thermal shock resistance, and visual inspection. For export orders, bricks are packed carefully to reduce breakage during long-distance transportation. Wooden pallets, moisture-proof packaging, labels, and customized marks can be arranged according to project requirements.
Certificates and Patents
JHYRef is certified under ISO 9001, ISO 14001 and ISO 45001 management systems, reflecting standardized quality control, environmental management and occupational health and safety practices throughout production.
Our patented refractory-related technologies and standardized production control help support stable product quality, responsible manufacturing and reliable long-term supply.
Technical Support & Services
Refractory technicians, refractory installation drawings, refractory bricks and castables, refractory masonry services, refractory mixes and precast cell, special shaped bricks, insulation materials, installation supervision, accident investigation and resolution, and other customized services tailored to your specific requirements.
