Introduction to the classification of high alumina refractory bricks according to the content of Al2O3

High alumina refractory bricks are divided into three grades according to the content of Al2O3: Class I (Al2O3>75%); Class II (Al2O3 is 60%~75%); Class III (Al2O3 is 48%~60%). According to the mineral composition, it can be divided into: low mullite (including sillimanite) and mullite (Al2O3 is 48%~71.8%), mullite-corundum and corundum-mullite (Al2O3 is 71.8%~95%), corundum (Al2O3 is 95%~100%) and other refractory bricks.