POSCO Holdings Inc.
METHOD FOR PRODUCING ALLOY STEEL

Abstract:

Provided is a method for producing steel including: preparing a first molten steel and a manganese-containing melt; supplying a nitrogen gas into a storage to blow nitrogen into the melt received in the storage and thereby adjusting a nitrogen content (wt %) in the melt to a required nitrogen content (wt %); and mixing the melt and the first molten steel to produce a second molten steel containing manganese and nitrogen. Since nitrogen is not blown while melting large amounts of solid materials, the oxidation of manganese due to a high temperature may be minimized or prevented. In addition, a large amount of solid material is not added, and a small amount of manganese-containing nonferrous metal or a FeMn ferroalloy is added, if necessary, into a produced melt in a molten state, and thus, a problem of temperature drop due to the input of the solid material may be minimized or prevented.