CGO Grain Oriented Electrical Steel M3/M4/M5/M6

Conventional Grain Oriented (CGO) Electrical Steel, also known as CRGO (Cold Rolled Grain Oriented) steel, is a premium 3% silicon-iron alloy. The grades M3, M4, M5, and M6 primarily represent distinct material thicknesses, each engineered to minimize core loss and maximize magnetic efficiency in transformers and large electrical equipment.

 

 

We produce cold rolled grain oriented plates (CRGO), also known as transformer plates. They are made of 3% silicon steel. Contains four levels of CRGO sheets:

AISI	ASTM	Thickness
		in	mm
M3	23G045	0.009	0.23
M4	27G051	0.011	0.27
M5	30G058	0.012	0.30
M6	35G066	0.014	0.35

 

 

Category			Silicon Content/%	Nominal Thickness/Mm	Lord To Use Way
Hot Rolled Silicon Steel (No Orientation)	Hot rolled low silicon steel(Motor Steel)		1.0~2.5	0.5	Household motors and micromotors
	Hot rolled high silicon steel(Transformer steel)		3.0~4.5	0.35,0.50	Transformer
Cold Rolled Electrical Steel	Cold rolled non-oriented electrical steel(Motor Steel)	Low carbon electrical steel	≤ 0.5	0.50,0.65	Small transformers and ballasts for household motors, micromotors
		Silicon steel	>0.5~3.5	0.35,0.50	Medium and large motors, generators and transformers
	Cold rolled grain oriented silicon steel(Transformer steel)	Ordinary oriented silicon steel	2.9~3.3	0.18,0.23,0.27 0.30,0.35	Large, medium and small transformers and ballasts
		High magnetic induction oriented silicon steel
Special Purpose Silicon Steel	Cold rolled grain oriented silicon steel strip		2.9~3.3	0.03,0.05,0.10	Pulse transformer, magnetic amplifier, high frequency transformer and electric welding machine
	Cold rolled non-oriented silicon steel strip		3.0	0.15,0.20	High-frequency motors and generators
	Cold rolled non-oriented silicon steel for magnetic switch		3.0	0.70	Relays and magnetic switches
	Cold rolled high silicon steel		6.5	0.1~0.5	High-frequency motors, transformers and magnetic shielding

 

 

The main application field of grain oriented electrical thin sheets is the iron core of power and distribution transformers. In addition, they are also used in the production of current transformers, voltage transformers, medium to large high-efficiency generators, reactors, magnetic screens, wound magnetic cores, audio transformers, etc.

 

 

CGO Grain Oriented Electrical Steel M3/M4/M5/M6 refers to conventional cold-rolled grain-oriented silicon steel grades classified primarily by their nominal thickness. The naming convention is straightforward: the thickness decreases as the grade number decreases - M3 measures 0.23mm, M4 is 0.27mm, M5 comes in 0.30mm, and M6 is 0.35mm. These four grades represent the backbone of the conventional grain-oriented electrical steel family, each carefully engineered to deliver optimal magnetic performance for different transformer sizes and efficiency requirements.

 

What Makes CGO Grain Oriented Electrical Steel Unique?

The defining characteristic of CGO Grain Oriented Electrical Steel lies in its crystal structure. Through the Goss texture control process, the silicon steel crystals are aligned nearly perfectly along the rolling direction. This grain orientation yields magnetic flux density increased by approximately 30% along the rolling direction compared to the transverse direction, while magnetic saturation is reduced by only about 5%. This directional advantage makes it possible to achieve extremely low core losses when the steel is properly oriented in transformer core assemblies.

 

Key properties include:

1. Low Core Loss: The most important quality indicator. Lower core loss means less energy wasted as heat, directly improving transformer efficiency.
2. High Permeability: Enhanced capacity to support magnetic fields, reducing magnetizing current requirements.
3. Low Magnetostriction: Minimal dimensional change during magnetization cycles, reducing audible noise and mechanical stress.
4. High Electrical Resistivity: Achieved through controlled silicon content, significantly reducing eddy current losses.

 

 

CGO Grain Oriented Electrical Steel M3/M4/M5/M6 uses the conventional designation system. Below is a quick cross-reference to equivalent grades from major global producers:

Thickness	Common Name	Baosteel (B)	WISCO (Q)	JFE (Japan)	POSCO (Korea)	Congent (Germany)	AK Steel (USA)
0.23 mm	M3	B23G110	23Q105/23Q110	23JGH100	23PH100	C110-23	M-3
0.27 mm	M4	B27G120	27Q120	27JG120	27PH120	C120-27	M-4
0.30 mm	M5	B30G120	30Q120	30JG120	30PH120	C120-30	M-5
0.35 mm	M6	B35G145	35Q145	35JG145	35PH145	C145-35	M-6

 

 

CGO Grain Oriented Electrical Steel M3/M4/M5/M6 remains the industry standard for conventional CRGO transformer core applications, offering a proven balance of low core loss, high magnetic induction, and cost-effectiveness across a wide range of transformer sizes. Whether you need M3 for high-efficiency distribution transformers, M4 for medium power applications, M5 for standard transformers, or M6 for economical large-core designs, GNEE delivers consistent quality, competitive pricing, and reliable technical support.

 

Ready to optimize your transformer core supply chain? Contact GNEE today to request a quote, discuss your specific grade and thickness requirements, or arrange a factory visit. Simply fill out the inquiry form below or email our sales team directly - let us provide the right CGO Grain Oriented Electrical Steel M3/M4/M5/M6 solution for your next project!

 

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FAQ

 

What is grain oriented electrical steel?

Grain-oriented electrical steel is a crucial material in the production of energy-efficient transformers and large, high-performance generators. In the form of laminated, wound, or punched sheets, it is the essential core material of distribution transformers, power transformers, and small transformers.

 

Why is CRGO used in transformers?

CRGO has lower hysteresis and eddy current losses due to its aligned grain structure, resulting in higher efficiency. This makes CRGO the go-to material for energy-efficient transformers and power distribution systems.

 

What is the difference between grain oriented and non grain oriented steel?

Non-grain-oriented electrical steel (NGOES) is mainly used in rotating equipment, for example, electric motors, generators and over frequency and high-frequency converters. Grain-oriented electrical steel (GOES), on the other hand, is used in static equipment such as transformers.

 

Can CRGO steel be used in electric motors?

- Electric Motors: CRGO steel is also used in the manufacturing of electric motors. The material's magnetic properties play a vital role in enhancing the motor's efficiency and performance.