Flux

Flux is a critical material or substance used in steelmaking, specifically during steel refining in a furnace. Flux is crucial in various steel making methods, such as the basic oxygen furnace (BOF) and the electric arc furnace (EAF). Its primary purpose is to facilitate the removal of impurities and unwanted elements from the molten iron to produce high-quality steel.

What is Flux?

Flux is a chemical substance added to molten iron or steel during steelmaking. It acts as a purifying agent and a slag-forming material. Fluxes are typically inorganic compounds, such as limestone (calcium carbonate) and dolomite (a mixture of calcium and magnesium carbonates). The choice of flux depends on the specific requirements of the steel production process.

Purification and Impurity Removal

One of the primary functions of flux is to aid in removing impurities and undesired elements from the molten iron. These impurities can include sulfur, phosphorus, and various non-metallic inclusions. When flux is added to the molten metal, it reacts with these impurities to form slag, which can be easily separated from the purified steel.

Control of Steel Composition

Flux can influence the chemical composition of the steel being produced. By carefully selecting the type and amount of flux added, steelmakers can adjust the steel’s composition to meet specific quality and performance requirements. This allows for producing steel with precise properties, such as strength, ductility, and corrosion resistance.

Temperature Control

In some cases, flux is used to control the temperature of the molten metal. Specific fluxing agents release heat when they react with impurities, which can help maintain the desired temperature within the furnace.