Ferromanganese

Ferromanganese is a ferroalloy with high manganese content (high-carbon ferromanganese can contain as much as 80% Mn by weight). It is made by heating a mixture of the oxides MnO2 and Fe2O3 , with Carbon (usually as coal and Coke) in either a blast furnace or an electric arc furnace-type system, called a submerged arc furnace. The oxides undergo carbothermal reduction in the furnaces, producing the ferromanganese. Ferromanganese is used as a deoxidizer for steel.

A North American standard specification is ASTM A99. The ten grades covered under this specification includes;

• Standard ferromanganese
• Medium-carbon ferromanganese
• Low-carbon ferromanganese

A similar material is a pig iron with high content of manganese, is called spiegeleisen, or specular pig iron.