Al2O3-MgO-C brick

The Al₂O₃-MgO-C Brick represents a sophisticated refractory solution developed for the most demanding steelmaking applications. Cavalry understands that modern steel production requires materials that withstand extreme temperatures, chemical attack, and mechanical stress. These alumina-magnesia-carbon refractories address these challenges through carefully balanced compositions and precise manufacturing processes.

The MgO-Al₂O₃-C system is widely used in ladle lining applications due to its excellent slag resistance and thermal shock stability. The combination of magnesia (MgO) and alumina (Al₂O₃) with carbon provides a unique set of properties that make these bricks suitable for aggressive metallurgical environments. The carbon content serves as a non-wetting agent, reducing slag penetration and improving corrosion resistance. The high alumina content contributes to excellent hot strength and resistance to thermal shock.

The six available grades (ZLMT-55 through ZLMT-80) provide options for different operational requirements. Lower alumina grades offer cost-effective solutions for less demanding applications, while higher alumina grades deliver superior performance in aggressive conditions. The ZLMT-80 grade with 80% Al₂O₃ and 85% combined MgO+Al₂O₃ provides maximum corrosion resistance for the most challenging ladle applications. The ZLMT-55 grade with 55% Al₂O₃ offers a more economical option for standard applications where extreme performance is not required.

The physical properties vary across the grade range. Bulk density increases from 2.95 g/cm³ in lower grades to 3.2 g/cm³ in the highest grade, providing greater density for improved corrosion resistance. Apparent porosity remains low at 7-8% for grades through ZLMT-75, increasing slightly to 10% for ZLMT-80. Cold crushing strength ranges from 35 MPa in lower grades to 45 MPa in higher grades, ensuring adequate structural integrity during installation and service.

These bricks are typically used in steel ladle sidewalls, slag lines, and ladle bottoms where slag attack is most aggressive. The combination of high temperature resistance, chemical stability, and thermal shock resistance makes these refractories suitable for modern steelmaking processes including vacuum degassing, ladle refining, and continuous casting operations.

Product highlights

Six Grade Options for Application Flexibility
The Al₂O₃-MgO-C brick range includes six grades from ZLMT-55 to ZLMT-80 with Al₂O₃ content from 55% to 80%. This range allows steelmakers to select the appropriate grade for specific operational requirements, balancing performance and cost. Lower grades provide economical solutions while higher grades deliver maximum performance for demanding applications.

Excellent Slag Resistance
The MgO-Al₂O₃-C composition provides outstanding resistance to slag attack in ladle applications. The carbon content acts as a non-wetting agent that reduces slag penetration and extends service life. The high alumina content contributes to chemical stability in basic slag environments. This combination delivers superior durability in aggressive metallurgical conditions.

Superior Thermal Shock Stability
The alumina-magnesia-carbon system exhibits excellent thermal shock resistance, essential for ladle applications where bricks experience rapid temperature changes during filling and emptying. The thermal shock stability reduces cracking and spalling, extending refractory service life and improving operational reliability.

High Bulk Density for Corrosion Protection
Bulk density ranges from 2.95 to 3.2 g/cm³ across the grade range, with higher grades providing greater density for improved corrosion resistance. The dense structure reduces slag penetration and slows the corrosion process, extending lining life and reducing maintenance frequency.

Low Apparent Porosity
Apparent porosity of 7-10% provides a dense structure that resists slag penetration and chemical attack. The low porosity contributes to extended service life by reducing the pathways for corrosive slag to penetrate the brick structure. The dense structure also supports better thermal conductivity and thermal shock performance.

High Cold Crushing Strength
Cold crushing strength ranges from 35 to 45 MPa across the grade range, ensuring adequate structural integrity during installation and service. The higher strength in premium grades provides additional resistance to mechanical stress during operation and handling.

Combined MgO+Al₂O₃ Content
The combined MgO+Al₂O₃ content ranges from 80% to 85%, ensuring high purity and consistent refractory performance. The high combined oxide content contributes to chemical stability and resistance to slag attack. The balanced composition provides optimal properties for steel ladle applications.

Proven Performance in Steelmaking
Al₂O₃-MgO-C bricks have demonstrated reliable performance in various steelmaking applications including ladle sidewalls, slag lines, and bottoms. The proven track record provides confidence in performance and service life.