(1) Used as deoxidizer and alloying agent in steelmaking industry. In order to obtain qualified steel and ensure the quality of steel, deoxidation must be carried out at the last stage of steelmaking. The chemical affinity between silicon and oxygen is very high. Therefore, ferrosilicon is a strong deoxidizer for steelmaking, used for precipitation and diffusion. Deoxygenation. Adding a certain amount of silicon in steel can significantly improve the strength, hardness and elasticity of steel, thus smelting structural steel (containing 0.40-1.75% silicon), tool steel (containing SiO.30-1.8%), spring steel (containing SiO.40-2.8%) and silicon steel for transformer (containing 2.81-4.8% silicon), ferrosilicon is also used as alloying agent.
In addition, in the steelmaking industry, the use of ferrosilicon powder at high temperatures releases a large amount of heat, which is usually used as a heating agent for the ingot cover to improve the quality and recovery of the ingot.
(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, easier to melt and smelt, has excellent casting properties and better seismic performance than steel, especially ductile iron, whose mechanical properties are close to or close to steel. Mechanical behavior. Adding a certain amount of ferrosilicon to cast iron can prevent the formation of carbides in iron. Promote the precipitation and spheroidization of graphite. Therefore, in the production of nodular cast iron, ferrosilicon is an important inoculant (conducive to precipitating graphite) and nodulizer.
(3) Used as reducing agent in ferroalloy production. Not only is the chemical affinity between silicon and oxygen high, but also high silicon ferrosilicon has very low carbon content. Therefore, high silicon ferrosilicon (or siliceous alloy) is a commonly used reducing agent in the production of medium and low carbon ferroalloys in ferroalloy industry.
(4) Used in other fields. Fine or atomized ferrosilicon powder can be used as suspension phase in mineral processing industry. It can be used as a coating for electrodes in the electrodes manufacturing industry. High silicon ferrosilicon can be used in chemical industry to produce products such as siloxane.
In these applications, iron and steel industry, casting industry and ferroalloy industry are the largest users of ferrosilicon. They consume more than 90% of ferrosilicon. Among all grades of ferrosilicon, 75% of ferrosilicon is most widely used. In the steelmaking industry, for every ton of steel produced, about 3-5 kg of ferrosilicon is consumed. Ferrosilicon grade and chemical composition