What Is The Electrical Steel in Transformer Core?

Electricity is the lifeblood of the modern world. As our world expands and the needs of our society grow, so too grows the need to develop more efficient transformers, generators and motors. These technologies are critical to increasing the efficacy of our power grids and the sustainability of our planet. The first step toward making these ecological and technological advancements is the development of more efficient electrical steels.

Electrical steel is the essential component for electromagnetic machines. It is used to create magnetic cores that help power transformers, power generators, and more. It's called by many names – lamination steel, silicon steel, transformer steel, and silicon electrical steel – but all of these terms share in their unique magnetic properties.

Electrical steel is usually manufactured in the form of cold-rolled strips, generally referred to as laminations. In the transformer core assembly process these thinly cut laminations are stacked together to form the core.

THE CHEMISTRY OF ELECTRICAL STEELS

Electrical steel is steel that has been alloyed with iron and silicon. Silicon is the most important alloyed element in electrical steel, as it provides the electrical resistance in the material. This resistance decreases in incoming eddy currents, which in turn leads to less core loss. Additionally, manganese and aluminum can be added to the material.

The purity of the material is paramount. Sulfur, oxides, nitrides, and carbides all decrease the magnetic permeability of the steel, and will also degrade the efficacy of the core over time. In order to reduce loss, transformer core manufacturers often use an annealing furnace to remove these harmful contaminants.

CRGO electrical steel