Non-grain oriented electrical steel is also known as silicon steel, laminate, core and electrical steel. This special steel has certain magnetic properties, such as high permeability or low hysteresis loss. The core steel is magnetized and then demagnetized. This causes it to heat up and absorb energy, which results in power loss. To reduce power loss, electrical steels must have some iron loss. You can also design electrical steels with high permeability to reduce the amount of electrical current required to produce magnetism. An iron alloy, electrical steels are usually cold-rolled strips with a portion of silicon, manganese or aluminum added to their melt. Each electrical steel manufacturer uses its own formula to make different grades. However, these grades are controlled by standards set by organizations such as the American Society for Testing and Materials (ASTM), the European Standard (EN), and the American Iron and Steel Institute. The American Iron and Steel Institute (AISI) is the common nomenclature reference in the U.S. The AISI standard for electrical steel is now obsolete and has been replaced by the ASTM standard.
Let’s look at why engineers still use electrical steels and if in some cases they are missing out.
Electrical steels are known by many names.
Laminated Steel Sheets
Silicon-steel electrical steel
Silicon Steel
Relay steel
Transformer steel
It is an iron alloy with specific magnetic properties, despite its name. Laminated iron cores are made using the laminated stacking technique. This is also used in the stators, rotors and transformers of electric motors. It is difficult to use electrical lamination to make individual round parts.
Electrical steel has many advantages
- Cost is usually an issue
The cost of silicon steel sheets is only 50-60 cents per kilogram and the stamping process can be done at a very low cost. Considering production and materials, electrical steel is often more cost effective than powder metallurgy.
The important thing is to weigh the benefits of powdered steel against the higher cost.
- Properties
The many mechanical properties of silicon steel can be used for a variety of performance reasons.
Low power loss per cycle (frequencies below 500 Hz)
Low iron loss
High permeability
In some cases, such as conventional motors, motor laminated steel is clearly a better choice than soft magnetic powders. The main reasons? Torque and energy consumption.