Brown fused Alumina known as “artificial corundum” or “alumina grit”. Brown fused alumina is produced from bauxite, charcoal, iron chip by being fused under high temperature in an electric arc furnace. It is characterized by high toughness and has a micro hardness of 2000-2200kg/mm2. The abrasive tools made by brown fused alumina are suitable for grinding carbon steel, normal alloy steel, malleable cast iron and hard bronze, etc. Brown fused alumina can also be used for making fine quality refractory etc.
Brown Fused Alumina (refractory)
|
Grit Size
|
AL2O3
MIN
|
SiO2
MAX
|
TiO2
MAX
|
Fe2O3
MAX
|
|
0-50mm
|
95%
|
1.5%
|
1.5-3.8%
|
0.5%
|
|
0-1mm
|
95%
|
1.5%
|
1.5-3.8%
|
0.5%
|
|
1-3mm
|
95%
|
1.5%
|
1.5-3.8%
|
0.5%
|
|
3-5mm
|
95%
|
1.5%
|
1.5-3.8%
|
0.5%
|
|
5-8mm
|
95%
|
1.5%
|
1.5-3.8%
|
0.5%
|
Physical Performance Index
|
Item
|
Index
|
|
Color
|
Brown
|
|
Crystal shape
|
Trigonal
|
|
Hardness(mohs)
|
≥9.0
|
|
Melting Point (°C)
|
2250
|
|
True density (g/cm3)
|
≥3. 90
|
|
Linear Expansion Coefficient(0—1600°C)
|
7—9
|