Performance of corundum bricks

Corundum bricks are high-performance refractory materials with α-Al₂O₃ (corundum) as the main crystalline phase and an alumina content typically greater than 90%. Due to their excellent physicochemical properties, they are widely used in key components of high-temperature industries such as steel, petrochemicals, and glass.

Lianxin- corundum brick

1. Excellent High-Temperature Resistance

Corundum bricks possess extremely high refractoriness, typically reaching 1750℃ to 1830℃. Their load-bearing softening initiation temperature is also generally higher than 1700℃. This means that they maintain structural stability even at high temperatures close to their melting point (2050℃), resisting softening and deformation, making them ideal lining materials for various ultra-high-temperature kilns.

2. Outstanding Mechanical Properties and Erosion Resistance

Corundum bricks have high mechanical strength, with a maximum compressive strength of 340MPa at room temperature, and some high-purity products exceeding 100MPa. Simultaneously, their extreme hardness (Mohs hardness of 9, second only to diamond) provides excellent wear resistance, effectively resisting the erosion of high-speed airflow and materials. Furthermore, its dense structure and low porosity effectively block the penetration and erosion of molten slag, molten metal, and molten glass, exhibiting extremely high chemical stability.

3. Performance Shortcomings and Optimization

Despite its excellent performance, dense corundum bricks have relatively poor thermal shock resistance (the ability to resist rapid temperature changes without cracking), which is its main weakness. To improve this property and enhance erosion resistance, industrial applications often optimize this by introducing additives such as ZrO₂ (zirconium corundum brick) or Cr₂O₃ (chromium corundum brick). For example, adding an appropriate amount of Cr₂O₃ can significantly improve the material’s resistance to molten slag erosion and thermal shock resistance while maintaining high-temperature resistance.

4. Key Application Areas

Based on the above properties, corundum bricks are widely used as working linings in equipment such as blast furnaces, ladle refining furnaces, glass melting furnaces, petrochemical gasification furnaces, and carbon black reactors, significantly extending equipment life and ensuring stable production operation.