is a neutral to weakly basic refractory material with synthetic spinel (MgO·Al₂O₃) as the primary crystalline phase. It is manufactured from high-purity fused magnesia (MgO ≥95%) and pre-synthesized spinel aggregates via high-pressure forming and sintering at 1750–1800°C. Its key advantages include **chromium-free eco-friendliness** (replacing magnesia-chrome bricks) and **exceptional thermal shock resistance.  

Key Properties  

High-Temperature Performance：  

Refractoriness ≥1900°C, load softening point 1650–1700°C (superior to conventional magnesia bricks);  

Low thermal expansion (7.0–8.5×10⁻⁶/K), excellent thermal shock resistance (>20 cycles, 1100°C water cooling).  

Corrosion Resistance:  

Resists alkaline slag, iron oxide slag, and cement clinker penetration;  

Low thermal conductivity (2.5–3.0 W/(m·K)), enhancing energy efficiency.  

Mechanical Strength:  

Cold crushing strength 50–70 MPa, hot modulus of rupture >6 MPa (1400°C).  

Primary Applications  

Cement Industry: Replaces magnesia-chrome bricks in rotary kiln transition zones (superior spalling resistance); modified versions required for burning zones to improve coating adherence;  

Steelmaking: Ladle linings, refining furnace linings (30% longer service life against slag erosion);  

Environmental Compliance: Eliminates hexavalent chromium pollution, meeting standards like EU RoHS.  

Technical Note: Composition modifications (e.g., adding hercynite) address brittleness in cement kiln burning zones.