Electric-furnace corundum (fused aluminium oxide)

Corundum (aluminium oxide) has been synthetically produced since the beginning of the 20th century. The synthetic corundum (normal corundum brown) is produced by reducing smelting of bauxite in an electric arc furnace at a temperature of over 2,000 °C. Unwanted accompanying substances are reduced by adding iron filings and coke. A brown corundum is produced.

The so-called white-fused alumina develops later in the process. The raw material used for its manufacture is calcined alumina (aluminium oxide), which is acquired from bauxite using the Bayer method. This is melted in an electric arc furnace to form white-fused alumina (99.7% Al2O3).

Pink aluminium oxide or ruby corundum is produced by specific addition of chromium oxide.

Here you can find out more about the different types of corundum (aluminium oxide) and request data sheets on them: