What is Ferrosilicon?

What is Ferrosilicon?

What is Ferrosilicon? Ferrosilicon is an alloy of iron and silicon. Ferrosilicon is an iron-silicon alloy made by smelting in an electric furnace using coke, steel scraps, and quartz (or silica) as raw materials. It is an important alloy variety in the smelting industry.

It is an iron-silicon alloy made from coke, steel scraps, and quartz (or silica) by smelting in an electric furnace (Ferrosilicon Furnace). It is widely used in the steel industry, foundry industry, and other industrial production.

Ferrosilicon Application

1. Used as deoxidizer and alloying agent in steelmaking industry. To obtain steel with qualified 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 very large, so ferrosilicon is a strong 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 the steel. Therefore, it is widely used in smelting structural steel (containing 0.40-1.75% silicon), tool steel (containing SiO.30-1.8%), spring steel, etc. Ferrosilicon is also used as an alloying agent when making silicon steel for transformers (containing SiO.40-2.8%) and silicon steel for transformers (containing silicon 2.81-4.8%). At the same time, 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. It is particularly suitable for the deoxidation requirements of continuous casting molten steel. The practice has proved that ferrosilicon not only meets the deoxidation requirements of steelmaking but also has desulfurization performance and the advantages of high specific gravity and strong penetration.

In addition, in the steelmaking industry, ferrosilicon powder is often used as a heating agent for steel ingot caps to improve the quality and recovery rate of steel ingots, taking advantage of its characteristic of releasing a large amount of heat when sintered at high temperatures.

2. Used as inoculant and spheroidizer in the 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 is much more resistant to shock than steel. In particular, the mechanical properties of ductile iron reach or approach those 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. Therefore, in the production of ductile iron, ferrosilicon is an important inoculant (to help precipitate graphite) and spheroidizer. 

3. Used as reducing agent in ferroalloy production. Not only is there a strong chemical affinity between silicon and oxygen, but high-silicon ferrosilicon also has a very low carbon content. Therefore, high-silicon ferrosilicon (or siliceous alloy) is a common reducing agent in the ferroalloy industry when producing low-carbon ferroalloys.

4. 75# ferrosilicon is often used in the high-temperature smelting process of magnesium metal in the Pijiang process to replace the magnesium in CaO.MgO. Every ton of magnesium metal produced consumes about 1.2 tons of ferrosilicon. Magnesium metal production plays a big role.

5. Use in other aspects. Ground or atomized ferrosilicon powder can be used in the mineral processing industry as a suspended phase. In the welding rod manufacturing industry, it can be used as a coating for welding rods. High silicon ferrosilicon can be used in the chemical industry to make products such as silicone.

Among these uses, the steelmaking, foundry, and ferroalloy industries are ferrosilicon's largest users. Together they consume more than 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 ton of steel produced.