Stal dynamnaya 2212, Dnepropetrovsk region.

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Transformer steel, also known as dynamic steel, transformer steel and silicon electrotechnical steel.

Alloying is not made with the pure element silicon, but with ferrosilicon. This substance is an alloy of FeSi with iron. Alloying of Si steel allows oxygen to be removed from the metal, the element that has the greatest negative effect on the magnetic properties of Fe. A reaction occurs to reduce iron from its oxides, with the resulting formation of silicon oxide, which partially turns into slag.(//tractor-service.com)

The second positive effect from the introduction of silicon into steel is associated with the release of cementite (Fe3C) from the metal, which is replaced by the graphite that is formed. Both compounds, iron oxide and cementite, increase the coercive force in the metal, which leads to an increase in hysteresis losses. Moreover, alloying iron with silicon with a concentration of Si higher than 4% also contributes to the reduction of eddy current losses, which is due to the increase in the specific electrical resistance of electrical steel relative to its grades not alloyed with silicon.

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