Uses And Characteristics Of Ferro Silicon Alloy

Uses and characteristics of ferro silicon alloy

(1) Used as a deoxidizer and alloying agent in the steelmaking industry. In order 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 ferro silicon is a strong deoxidizer for precipitation and diffusion deoxidation in steelmaking. Adding a certain amount of silicon to steel can significantly improve the strength, hardness and elasticity of steel. Therefore, ferro silicon is also used as an alloying agent when 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 transformers (containing 2.81-4.8% silicon).

In addition, in the steelmaking industry, ferro silicon 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 the characteristic that it can release a large amount of heat when burned at high temperatures.

(2) Used as an inoculant and spheroidizer in the 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 properties and much better vibration resistance than steel, especially ductile iron, whose mechanical properties reach or approach those of steel. Adding a certain amount of ferro silicon 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 (helping to precipitate graphite) and spheroidizer.

(3) Used as a reducing agent in iron. Not only is the chemical affinity between silicon and oxygen very large, but the carbon content of high-silicon ferro silicon is also very low. Therefore, high-silicon ferro silicon (or siliceous alloy) is a relatively common reducing agent in the production of low-carbon ferroalloys in the ferro alloy industry.
(4) Uses in other aspects. Ground or atomized ferro silicon powder can be used as a suspension phase in the mineral processing industry. It can be used as a coating for welding rods in the welding rod manufacturing industry. High-silicon ferro silicon can be used to manufacture silicone and other products in the chemical industry.

Among these uses, the steelmaking industry, foundry industry and ferroalloy industry are the largest users of ferro silicon. They consume more than 90% of ferro silicon in total. Among various grades of ferro silicon, 75% ferrosilicon is currently the most widely used. In the steelmaking industry, about 3-5kg of 75% ferro silicon is consumed for every ton of steel produced.