High-alumina refractory bricks are a type of refractory material, with the main component being AL2O3. If the Al2O3 content exceeds 90%, it is called corundum brick. Due to varying resources, standards across countries are not entirely uniform. For instance, European countries stipulate that the minimum Al2O3 content for high-alumina refractory materials is 42%. In China, high-alumina bricks are typically categorized into three grades based on the Al2O3 content: Grade I - Al2O3 content > 75%; Grade II - Al2O3 content 60-75%; Grade III - Al2O3 content 48-60%.