The Differences Between Brown Corundum And Black Corundum

- May 02, 2018 -

The Differences Between Brown Corundum And Black Corundum

Brown corundum and black corundum are both widely used in abrasives and refractory materials, grinding and polishing materials. However, there are differences between brown corundum and black corundum. The differences are listed below.

1. Color

Brown corundum is in dark brown, while black corundum is in black color.

2. Raw Materials

Brown corundum(brown fused alumina) is made by high-quality bauxite, while black corundum (black fused alumina) is made by bauxite and Fe2o3.

3. Alumina Content

Brown corundum content 95% min of alumina, but black corundum has 80% max of alumina.

4. Density

Brown corundum true density (3.90g/cm3). While black corundum true density (3.50g/cm3).

5. Melting Point

Brown corundum has melting point at 2200 Celsius degree. Black corundum has the melting point of 1850 Celsius degree.

6. Hardness

Brown corundum with hardness of 9.0 is harder that black corundum.

7. Usage

Brown corundum and black corundum can both used in the manufacture of coated abrasives and resin bonded grinding wheels. Due to the high content of Fe2o3, black corundum can’t used for making vitrified grinding wheels.