Transformer steel with carlite coating, Dnipropetrovsk region.

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Depending on the required properties, electrical steel contains different amounts of silicon.
Depending on the production technology, electrotechnical steels are divided into cold-rolled (isotropic or anisotropic; the amount of silicon is up to 3.3%) and hot-rolled (isotropic; the amount of silicon is up to 4.5%).(//tractor-service.com)
Aluminum (up to 0.5%) can often be found in electrical steel as an alloyingadditive.
Sometimes electrotechnical steels are conditionally divided into dynamic steel (0.8-2.5% silicon) and transformer steel (3-4.5% silicon)

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