The use of ferrosilicon

(1) Used as a deoxidizer and alloying agent in the steelmaking industry. In order to obtain qualified steel with chemical composition and ensure the quality of steel, deoxidation must be carried out in the final stage of steelmaking. The chemical affinity between silicon and oxygen is high, so ferrosilicon is a strong deoxidizer for precipitation and diffusion deoxidization in steelmaking. Adding a certain amount of silicon to steel can significantly improve its strength, hardness, and elasticity. Therefore, ferrosilicon is also used as an alloying agent in smelting structural steel (containing 0.40-1.75% silicon), tool steel (containing 30-1.8% SiO), spring steel (containing 40-2.8% SiO), and transformer silicon steel (containing 2.81-4.8% silicon). Simultaneously improving the morphology of inclusions and reducing the content of gas elements in molten steel is an effective new technology to improve steel quality, reduce costs, and save iron. Especially suitable for the deoxygenation requirements of continuous casting molten steel, practice has proven that ferrosilicon not only meets the deoxygenation requirements of steelmaking, but also has desulfurization performance and advantages such as high specific gravity and strong penetration.
In addition, in the steelmaking industry, utilizing the characteristic of silicon iron powder being able to release a large amount of heat during high-temperature olefin firing, it is often used as a heating agent for steel ingot caps to improve the quality and recovery rate of steel ingots.
(2) Used as an inoculant and spheroidizer in the cast iron industry. Cast iron is an important metal material in modern industry, which is cheaper than steel, easy to melt and smelt, and has excellent casting performance and much better seismic resistance than steel. Especially nodular cast 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 and promote the precipitation and spheroidization of graphite. Therefore, ferrosilicon is an important inoculant (helping to precipitate graphite) and spheroidizing agent in the production of ductile iron.
(3) Used as a reducing agent in ferroalloy production. Not only is the chemical affinity between silicon and oxygen high, but the carbon content of high silicon ferrosilicon is also very low. Therefore, high silicon ferrosilicon (or siliceous alloys) is a commonly used reducing agent in the production of low-carbon ferroalloys in the ferroalloy industry.
(4) 75 # ferrosilicon is often used in the high-temperature smelting process of metal magnesium in the Pijiang process of magnesium smelting. Replacing the magnesium in CaO.MgO consumes about 1.2 tons of ferrosilicon for each ton of metal magnesium produced, which plays a significant role in the production of metal magnesium.
(5) For other purposes. Silicon iron powder, which has been finely ground or atomized, can be used as a suspended phase in the mineral processing industry. It can be used as a coating for welding rods in the welding rod manufacturing industry. High silicon ferrosilicon can be used in the chemical industry to manufacture products such as silicone.

Among these uses, the steelmaking industry, casting industry, and ferroalloy industry are the largest users of ferrosilicon. They collectively consume over 90% of ferrosilicon. Among various grades of ferrosilicon, 75% ferrosilicon is currently the most widely used. In the steelmaking industry, approximately 3-5 kg of 75% ferrosilicon is consumed for every 1 ton of steel produced.