Silicon ——it can increase the hardness of steel, but the plasticity and toughness are reduced. Steel used for electrical engineering contains a certain amount of silicon, which can improve soft magnetic properties.
Silicon exists as a reducing agent and deoxidizer in the steelmaking process, so killed steel generally contains 0.15~0.30% silicon. If the silicon content in the steel exceeds 0.5%, even if it contains silicon-containing alloying elements, silicon can significantly increase the elastic limit, yield point and tensile strength of the steel, so it is often used as spring steel. High alloy content can improve the heat resistance and corrosion resistance of steel. Low carbon steel with a silicon content of 1% to 4% has extremely high magnetic permeability and is often used in the electrical industry and silicon steel sheets. However, as the silicon content increases, the welding performance of the steel will be reduced.
It was discovered in 1900 by Hadfield (1926) that the addition of silicon improves the soft magnetic properties of steel. As Si content increases, magnetic permeability increases, due to low magneto-crystalline anisotropy and low magnetostrictive coefficients (Bozorth, 1951).
The magnetic permeability of iron is thousands to tens of thousands times higher than the magnetic permeability of air. Adding silicon to iron can further increase the maximum magnetic permeability of iron, generate a stronger magnetic field during magnetization, reduce losses at the same time, and improve the efficiency of electrical energy. Generation, transmission and use efficiency, therefore electrical steel produced with silicon and iron as the main components is mainly used as core material and is widely used in industries such as power, electronics, aerospace, military industry and so on.
The good properties of electrical steel were first discovered in 1900. After going through the production stages of hot rolling and cold rolling, it has continued to develop in the direction of higher performance such as high magnetic induction and low iron loss. In recent years, with the transformation of the world's energy structure and energy conservation, With the continuous acceleration of the emission reduction process, electrical steel has become one of the indispensable raw material products for the high-quality development of the country and the low-carbon and green life of mankind.
