Use of ferrosilicon
1. Used as deoxidizer and alloying agent in steelmaking industry. In order to obtain the chemical composition of qualified steel and ensure the quality of steel, in the final stage of steelmaking must be deoxidized, the chemical affinity between silicon and oxygen is very large, so ferrosilicon is a strong deoxidizer for precipitation and diffusion in steelmaking. Adding a certain amount of silicon to steel can significantly improve the strength, hardness and elasticity of steel, so when smelting structural steel (containing silicon 0.40-1.75%), tool steel (including SiO.30-1.8%), spring steel (including SiO.40-2.8%) and transformer silicon steel (containing silicon 2.81-4.8%), Ferrosilicon is also used as an alloying agent. At the same time, improving the shape of inclusions and reducing the content of gas elements in molten steel is an effective new technology to improve steel quality, reduce cost and save iron. It is especially suitable for continuous casting steel deoxidation requirements. Practice has proved that ferrosilicon not only meets the deoxidation requirements of steelmaking, but also has desulfurization performance and has the advantages of heavy ratio and strong penetration.
In addition, in the steelmaking industry, the use of ferrosilicon powder at high temperature can release a lot of heat, which is often used as ingot cap heating agent to improve the quality and recovery of ingot.
2. Used as inoculant and nodulator in cast iron industry. Cast iron is an important metal material in modern industry, it is cheaper than steel, easy to melt and smelt, has excellent casting performance and much better earthquake resistance than steel. In particular, ductile iron, its mechanical properties reach or approach the mechanical properties of steel. Adding a certain amount of ferrosilicon to cast iron can prevent the formation of carbides in iron and promote the precipitation and spheroidization of graphite, so in the production of ductile iron, ferrosilicon is an important inoculant (to help precipitate graphite) and spheroidizing agent.
3. Used as reducing agent in ferroalloy production. Not only the chemical affinity between silicon and oxygen is very large, but also the carbon content of high-silicon iron silicon is very low. Therefore, high-silicon ferrosilicon (or siliceous alloy) is a commonly used reducing agent in the ferroalloy industry when producing low-carbon ferroalloys.
4, 75# ferrosilicon in the Pijiang method of magnesium smelting is often used in the high temperature smelting process of magnesium metal, the magnesium in CaO.MgO is replaced, each production of a ton of magnesium metal to consume about 1.2 tons of ferrosilicon, magnesium metal production plays a great role.
5. Other uses. The fine or atomized ferrosilicon powder can be used as a suspended phase in the mineral processing industry. In the welding rod manufacturing industry can be used as welding rod coating. High silicon iron silicon is used in the chemical industry to make products such as silicone.
Among these uses, the steelmaking industry, the casting industry and the ferroalloy industry are the largest users of ferrosilicon. Together, they consume more than 90% of the ferrosilicon. In a variety of different grades of ferrosilicon, the most widely used is 75% ferrosilicon. In the steelmaking industry, about 3-5kG 75% of ferrosilicon is consumed per 1t of steel produced.
