High alumina brick is a kind of refractory material. The main component of this refractory brick is Al2O3.

If the Al2O3 content is higher than 90%, it is called corundum brick. Due to different resources, national standards are not completely consistent. For example, European countries stipulate that the lower limit of Al2O3 content for high aluminum refractory is 42%. In China, the Al2O3 content in high-alumina bricks is usually divided into three grades: Ⅰ etc.-Al2O3 content> 75%; Ⅱ etc.-Al2O3 content is 60 ~ 75%; Ⅲ etc.-Al2O3 content is 48 ~ 60%.