Silicon steel, also known as electrical steel, lamination steel or transformer steel, is a kind of steel with special organizational structure and magnetic properties.

As you may know, there are two forms of silicon steel: oriented silicon steel, or CRGO, and non-oriented silicon steel, or CRNGO.

So what is the difference between CRGO and CRNGO? In this article, you’ll learn their difference.

1. Different properties

Oriented silicon steel, also known as CRGO, is an important ferrosilicon alloy used in the transformer (core) manufacturing industry.

Non-oriented silicon steel, or CRNGO is a ferrosilicon alloy with very low carbon content. Its grains are randomly oriented in the deformed and annealed steel plate. 

LEFT: Transformer; Right: Motor Core

 2. Different characteristics

The magnetism of grain-oriented silicon steel has strong directionality, with the lowest iron loss value in the rolling direction, the highest magnetic permeability and high magnetic induction value under a certain magnetizing field. The silicon content of oriented silicon steel is about 3%, and the steel is required to have low oxide inclusion content and must contain some kind of inhibitor.

Non-oriented silicon steel is a ferro silicon alloy containing 0.8%-4.8% silicon. It is hot and cold rolled into silicon steel sheets with a thickness of less than 1mm. Adding silicon can increase the resistivity and maximum magnetic permeability of iron, and reduce coercive force, core loss and magnetic aging. 

crystallographic texture between CRGO and CRNGO/ sourcing: ScienceDerict

 3. Different production processes

Oriented silicon steel is smelted in an oxygen converter. The billet undergoes hot rolling, normalization, cold rolling, intermediate annealing and secondary cold rolling to the finished thickness, and then undergoes decarburization annealing and high-temperature annealing, and is finally coated with an insulating layer.

Non-oriented silicon steel: pre-desulfurization of molten iron, secondary desulfurization by adding Ca0+CaF: flux or rare earth elements and calcium during converter blowing. The boiling molten steel is decarburized by vacuum treatment and then further desulfurized. Ferrosilicon with low titanium and zirconium content is selected for alloying.

I hope this article can be helpful. If you have any questions, feel free to contact us.