Brown fused alumina is fused and crystalized under high temparaure from a mixture of bauxite and other materials. It is characterized by its high hardness, good toughness and sharp shapein size. Abrasives tools made of it are suitable for grindind metals of high-tensile strength such as carbon steel, general-purpose alloy steel, annealed malleable iron and hard bronze,etc. it also can be used as refractory materials. 化学成分 Chemical composition (%) 粒度Grit Size Al2O3 TiO2 SiO2 Fe2O3 CaO MgO F4-F80 95.59-97.5 2.0-3.8 ≤0.9 ≤0.15 ≤0.35 ≤0.5 F90-F150 94.5-97.5 2.0-3.8 ≤0.9 ≤0.15 ≤0.35 ≤0.5 F180-F220 93.5-96.5 2.0-3.8 ≤0.9 ≤0.15 ≤0.35 ≤0.5 F46 95.58 2.5 ≤0.8 ≤0.08 ≤0.28 ≤0.32