How is ferrosilicon made?
Ferrosilicon: An alloy of iron and silicon. (1) Used as deoxidizer and alloying agent in steelmaking industry. In order to obtain the qualified chemical composition of the steel and ensure the quality of the steel, in the final stage of steelmaking must be deoxidized, silicon and oxygen between the chemical affinity is great, so ferrosilicate is a strong deoxidizing agent used for precipitation and diffusion deoxidization. Adding a certain amount of silicon in the steel can significantly improve the strength, hardness and elasticity of the steel, so in the smelting of structural steel (containing silicon 0.40-1.75%), tool steel (containing Sio.30-1.8%), spring steel (containing Sio. 40-2.8%) and silicon steel for transformer (containing silicon 2.81-4.8%), Ferrosilicon is also used as an alloying agent. In addition, in the steel-making industry, the ferosilicon powder is often used as the ingot cap heating agent to improve the quality and recovery of the ingot, taking advantage of the characteristic that the ferosilicon powder can give off a lot of heat at high temperature. (2) Used as inoculant and spheroidizer in cast iron industry. Cast iron is an important metal material in modern industry. It is cheaper than steel, easy to melt and smelt, and has excellent casting performance and much better aseismic ability than steel. Ductile iron, in particular, has mechanical properties equal to or close to those of steel. Adding a certain amount of ferrosilicon in cast iron can prevent the formation of carbide in iron, promote the precipitation and spheroidization of graphite, so in the production of nodular cast iron, ferrosilicon is an important inoculant (to help the precipitation of graphite) and spheroidizer. (3) used as reducing agent in ferroalloy production. Not only is the chemical affinity between silicon and oxygen great, but the carbon content of high silicon ferrosilicon is very low. Therefore, high silicon ferrosilicon (or siliceous alloy) is a commonly used reducing agent in the production of low carbon ferroalloy in the ferroalloy industry. (4) for other purposes. Grinded or atomized ferrosilicon powder can be used as a suspended phase in the mineral processing industry. It can be used as coating for electrode in electrode manufacturing industry. High silicon ferrosilicon in the chemical industry can be used to manufacture silicone and other products. Among these applications, the steelmaking, foundry and ferroalloy industries are the largest users of ferrosilicate. Together, they consume more than 90% of ferrosilicon. In a variety of different grades of ferrosilicon, the most widely used is 75% ferrosilicon. In steelmaking industry, about 3-5kg75% ferrosilicon is consumed for each 1t of steel produced. The range of chemical composition Si Al Ca Mn Cr P S C is not greater than FeSi75Ai1.0-B 72.0-80.0 1 1 0.5 0.5 0.04 0.02 0.2 FeSi75Ai1.5-B 72.0-80.0 Ferrosilicon is widely used in steel industry, foundry industry and other industrial production. Ferrosilicon is an indispensable deoxidizer in steelmaking industry. In torch steel, ferrosilicate is used for precipitation deoxidation and diffusion deoxidation. Brick iron is also used as an alloying agent in steelmaking. Adding a certain amount of silicon to steel can significantly improve the strength, hardness and elasticity of steel, improve the magnetic permeability of steel, and reduce the hysteresis loss of transformer steel. Silicon in general steel 0.15%-0.35%, structure steel 0.40%-1.75%, tool steel 0.30%-1.80%, spring steel 0.40%-2.80%, stainless acid-proof steel 3.40%-4.00%, heat resistant steel 1.00%-3.00%, The silicon steel contains 2% ~ 3% or more silicon. High silicon ferrosilicon or siliceous alloys are used as reducing agents for the production of low carbon ferroalloys in the ferroalloy industry. Adding ferrosilicon to cast iron can be used as inoculant for nodular cast iron, and can prevent the formation of carbide, promote the precipitation of graphite and spheroidization, improve the performance of cast iron. In addition, ferrosilicon powder in the mineral processing industry can be used as a suspended phase, in the electrode manufacturing industry for electrode coating; High silicon ferrosilicon in the electrical industry can be used to prepare semiconductor pure silicon, in the chemical industry can be used to manufacture silicone, etc. In steelmaking industry, 3 ~ 5kg75% ferrosilicon is consumed for each ton of steel produced. Melting point: 75SiFe is 1300℃
