Different Type Of Brown Fused Aluminum Oxide
Brown fused alumina is produced by calcined bauxite, carbon and iron scrap in electric arc furnace at temperatures more than 2000°C. The main chemical composition of brown fused alumina is AL2O3,and small amount of Fe, Si, Ti, etc.According to various standard, BFA can be classified into several types based on the factors listed below.
1)Chemical composition Al2O3 content
Basically, BFA chemical content has three grade with 95%, 90%, 80-85% Al2o3. That is the main standard to divide BFA into first grade, second and third grade.
The different chemical content is due to the crystallization and precipitation in BFA smelting process. The middle part of electric arc furnace BFA is the best crystalline and high purity with 95% Al2O3. The upper of furnace BFA is 90% content, and 80-85% BFA is in the bottom of furnace. The price and usage are various due to the different chemical content.
BFA bulk density can be different due to using of the different crashing machine, such as BARMAC, BALL MILL and ROLLER machine. BFA made by BARMAC machine has higher bulk density and good grinding ability.
3) Smelting furnace
BFA can be divided into two different smelting furnace, tilting furnace and stable furnace. The biggest difference between tilting furnace and stable furnace is the chemical content of Tio2 and Sio2. Compared with the stable furnace BFA, the tilting furnace has higher Tio2 and lower Sio2. Tilting Furnace BFA is characteristic with high hardness and good grinding ability. It is widely used in vitrified grinding wheels and advanced refractory materials.
For eliminating the impurities in brown aluminum oxide, we have water washed, acid washed and wind washed brown fused alumina grain according to customer’s request.
5)Particle Size Standard
Abrasives are measured by different standards that define a limited range of particle sizes for each grade. The mainly standard are listed as follows.
ANSI stands for "American National Standards Institute".
FEPA stands for "Federation of European Producers of Abrasives Products".
JIS stands for "Japanese Industrial Standards".
GB: Chinese National Standard