MgO-CaO Brick

The MgO-CaO Brick represents a specialized refractory solution that combines the advantages of high-purity magnesia and calcium oxide for demanding steelmaking applications. Cavalry understands that modern steel production requires refractories that withstand aggressive slag attack while maintaining structural integrity at extreme temperatures. These magnesia-calcia refractories address these challenges through carefully balanced compositions and precise manufacturing processes.

The MgO-CaO system offers distinct advantages for steel ladle applications. The calcium oxide component provides enhanced resistance to low-basicity slags, which can be particularly aggressive to conventional magnesia-based refractories. Additionally, the CaO contributes to the removal of phosphorus and sulfur during ladle refining, supporting the production of high-quality steel grades. The free lime content can also absorb alumina inclusions, improving steel cleanliness. This combination of chemical stability and metallurgical functionality makes MgO-CaO refractories particularly valuable for secondary steelmaking applications where steel quality is critical.

The eight available grades provide flexibility for different operational requirements. The ZMG-20 grades (20A and 20B) with 18% CaO and 66-68% MgO offer balanced properties for standard ladle applications. The ZMG-25 grades (25A and 25B) with 23% CaO and 60-62% MgO provide increased calcia content for enhanced slag resistance. The ZMG-30 grades (30A and 30B) with 28% CaO and 58-60% MgO deliver higher calcia content for more demanding applications. The ZMG-40A with 38% CaO and 50% MgO and ZMG-50A with 48% CaO and 40% MgO offer maximum calcia content for specialized requirements where low-basicity slag resistance is paramount.

The physical properties are impressive across the product range. Bulk density ranges from 2.9 to 3.05 g/cm³, providing dense structures for corrosion protection. Apparent porosity of 14-15% offers good resistance to slag penetration while maintaining thermal shock resistance. Cold crushing strength of 50-55 MPa ensures excellent structural integrity during installation and service. The refractoriness under load of 1680-1700°C demonstrates the high-temperature capability of these refractories, suitable for the most demanding steelmaking applications.

Product highlights

Eight Grade Options for Application Flexibility
The MgO-CaO brick range includes eight grades with MgO content from 40% to 68% and CaO content from 18% to 48%. This range allows steelmakers to select the optimal CaO content for specific steel grades and slag conditions. Higher CaO grades provide enhanced resistance to low-basicity slags.

Superior Slag Resistance
The calcium oxide component provides outstanding resistance to low-basicity slags that can be aggressive to conventional refractories. The CaO content also contributes to phosphorus and sulfur removal during ladle refining. This dual functionality supports both refractory durability and steel quality.

Excellent Bulk Density
Bulk density ranges from 2.9 to 3.05 g/cm³ across the product range, providing dense structures for corrosion protection. Higher density grades offer maximum resistance to slag penetration. The consistent density supports predictable refractory performance.

Good Cold Crushing Strength
Cold crushing strength of 50-55 MPa across all grades ensures excellent structural integrity during installation and service. The high strength provides reliable handling characteristics and installation performance. The strength supports resistance to mechanical stress during operation.

High Refractoriness Under Load
Refractoriness under load of 1680-1700°C demonstrates the high-temperature capability of these refractories. The high refractoriness ensures dimensional stability at extreme temperatures. The thermal stability supports reliable performance in the most demanding steelmaking applications.

Controlled Apparent Porosity
Apparent porosity of 14-15% provides a balanced structure that resists slag penetration while maintaining thermal shock resistance. The consistent porosity supports predictable performance across different grades. The porosity control contributes to extended service life.

Low Impurities for High Purity
Total impurities are tightly controlled at 2.5-4% across the grade range, ensuring high purity and consistent refractory performance. The low impurity levels reduce the risk of contamination in high-quality steel grades. The high purity also contributes to improved slag resistance.

Metallurgical Benefits for Steel Quality
The CaO component contributes to the removal of phosphorus and sulfur during ladle refining. The free lime can also absorb alumina inclusions, improving steel cleanliness. These metallurgical benefits support the production of high-quality steel grades.

Proven Performance in Steelmaking
MgO-CaO bricks have demonstrated reliable performance in ladle linings and steelmaking vessels. The proven track record provides confidence in performance and service life.