Uses of ferrosilicon.
(1) Used as a deoxidizer and alloying agent in the steelmaking industry. In order to obtain chemically qualified steel and to ensure the quality of steel, deoxidation must be carried out in the final stage of steelmaking. The chemical affinity between silicon and oxygen is great, thus ferrosilicon is a stronger deoxidizer for steelmaking for precipitation and diffusion deoxidation. Adding a certain amount of silicon to steel can significantly improve the strength, hardness and elasticity of steel, and thus in the smelting of structural steel (containing 0.40-1.75% silicon), tool steel (containing SiO.30-1.8%), spring steel (containing SiO.40-2.8%) and transformer silicon steel (containing silicon 2.81-4.8%), ferrosilicon is also used as an alloying agent.
In addition, in the steel industry, the use of ferrosilicon powder in the high temperature olefin burning can give off a lot of heat this feature, often used as ingot cap heating agent to improve the quality of ingots and recovery rate.
(2) In the cast iron industry as inoculant and spheroidizing agent. Cast iron is an important metal material in the modern industry, it is cheaper than steel, easy to melt smelting, with excellent casting performance and much better than steel to get shock capacity, especially ductile iron, its mechanical properties to achieve or close to the mechanical properties of steel. The addition of a certain amount of ferrosilicon in cast iron can prevent the formation of carbide in iron, promote the precipitation of graphite and spheroidization, and thus in the production of ductile iron, ferrosilicon is an important inoculant (to help precipitate graphite) and spheroidizing agent.
(3) Used as a reducing agent in the production of ferroalloys. Not only is the chemical affinity between silicon and oxygen high, but the carbon content of high ferrosilicon silica is very low. Therefore high ferrosilicon (or siliceous alloy) is a relatively common reducing agent in the ferroalloy industry for the production of low carbon ferroalloys.
(4) Uses in other areas. Finely ground or atomised ferrosilicon powder can be used as a suspension phase in the mineral processing industry. It can be used as a coating for welding rods in the welding rod manufacturing industry. High ferrosilicon is used in the chemical industry to manufacture products such as silicones.
Of these uses, the steelmaking industry, the foundry industry and the ferroalloy industry are the largest users of ferrosilicon. Together they consume around 90% or more of ferrosilicon. Of the various grades of ferrosilicon, the most widely used by far is 75% ferrosilicon. In the steel industry, approximately 3-5 kg of 75% ferrosilicon is consumed per 1 t of steel produced.
