Ferro manganese is one type of iron alloy mainly composed of manganese and iron.The chemical properties of manganese are more active than iron.When add the manganese to molten steel,it can react with ferrous oxide to form the oxide slag which is insoluble in molten steel,the slag float on the molten steel surface,reduce the oxygen content in the steel.At the same time,the binding force between manganese and sulfur is greater than the binding force between iron and sulfur,after add the manganese alloy,the sulfur in the molten steel is easy to form a high melting point manganese alloy,the sulfur in the molten steel is easy to form a high melting point manganese sulfide with manganese and transfer into the furnace slag,thereby reducing the sulfur content in the molten steel and improving the forgeability and rollability of steel.Manganese can also increase the strength,hardenability,hardness and wear resistance of the steel.So the ferro manganese often use as the deoxidizer,desulfurizer and alloy additive in steel making and that makes it the most used iron alloy.