B23R085 0.23mm 0.85W/kg Grain-Oriented Silicon Steel coil

Parameter	Specification
Grade	B23R085
Steel type	High-permeability (Hi-B) grain-oriented silicon steel
Nominal thickness	0.23 mm
Width range (slit)	35 mm – 1250 mm (custom widths available)
Maximum core loss (P₁.₇/₅₀)	≤ 0.85 W/kg
Minimum magnetic induction (B₈)	≥ 1.88 T
Stacking factor (lamination factor)	≥ 97.5%
Density	7.65 kg/dm³
Resistivity (20°C)	approx. 50 µΩ·cm
Insulation coating	C5 (inorganic, T2/T3) or C6 (high adhesion)
Standard	IEC 60404-8-7, GB/T 2521, Baosteel enterprise standard
Coil weight	3 – 8 metric tons (per coil)
Edge condition (slit)	Burr ≤ 0.02 mm, no edge wave
Applications	Ultra-efficient distribution transformers, power transformers, reactors, instrument transformers

 

Click to learn more about GNEE grain-oriented silicon steel

 

B23R085 is a Hi-B grade with ultra-low core loss (0.85 W/kg) , extremely high magnetic permeability, and a thin 0.23mm gauge. It is specifically designed for large power transformers, high-efficiency distribution transformers, and other critical applications where every 0.1 W/kg reduction in core loss delivers significant annual energy savings.

 

 

Typical Chemical Composition (wt%) 

Element	Typical Range (%)	Role & Effect
Silicon (Si)	3.0% – 3.3%	Raises electrical resistivity → drastically lowers eddy current loss. Enables 0.85 W/kg core loss at 1.7T.
Carbon (C)	≤ 0.02%	Kept extremely low to prevent magnetic aging and increased hysteresis loss.
Manganese (Mn)	0.08% – 0.15%	Improves hot ductility during rolling.
Phosphorus (P)	≤ 0.015%	Minimized to avoid brittleness and degradation of magnetic properties.
Sulfur (S)	≤ 0.003%	Ultra-low sulfur is critical for developing a perfect Goss texture during secondary recrystallization.
Aluminum (Al)	≤ 0.005%	Tightly controlled; excess Al can form nitrides that interfere with grain growth.
Nitrogen (N)	≤ 0.002%	Low nitrogen prevents grain boundary embrittlement and maintains high permeability.

 

Why silicon content is critical:

Each 1% increase in silicon boosts electrical resistivity by ~15–20%, reducing eddy current losses proportionally. At 3.0–3.3% Si, B23R085 achieves an optimal balance: high resistivity to minimize core loss, while still maintaining sufficient mechanical strength for slitting, stamping, and core stacking. Compared to lower-Si grades (e.g., 2.8–3.0% Si), the slightly higher silicon content in B23R085 directly enables the 0.85 W/kg guaranteed loss value.

 

Insulation coating: Supplied with a C5 (inorganic phosphate + chromate-free) or C6 coating, providing high inter-laminar resistance (800–1000 V per layer) and excellent heat resistance during core annealing.

 

 

Best Uses of B23R085 0.85W/kg Grain-Oriented Silicon Steel Coil

The combination of 0.23mm thickness, 0.85 W/kg core loss, and high permeability (≥1.88 T) makes B23R085 silicon steel coil the material of choice for the most demanding electromagnetic applications.

 

High-Efficiency Distribution Transformers (15 kV – 36 kV, DOE/CEE Tier 2 compliant)

Utilities and OEMs require no-load losses as low as possible to meet energy efficiency regulations. At 0.85 W/kg, B23R085 reduces annual energy waste by over 15% compared to conventional 1.10 W/kg grades.

 

Medium & Large Power Transformers (36 kV – 230 kV, up to 100 MVA)

Hi-B grade ensures very high magnetic flux density, reducing core cross-section and overall transformer weight. The 0.23mm gauge minimizes eddy current losses even under moderate harmonic loads.

 

Reactors & Shunt Reactors (for power quality & HVDC systems)

The low magnetostriction of B23R085 reduces audible noise. The high permeability ensures stable inductance over a wide current range.

 

Instrument Transformers (CTs, VTs) and Special Applications

For metering and protection transformers where core saturation must be avoided, B23R085's high B8 (>1.88 T) provides a wide linear operating range.

 

High-Frequency Transformers (400 Hz – 1000 Hz, e.g., railway or aircraft converters)

The 0.23mm thickness reduces eddy current losses significantly at higher frequencies compared to 0.27mm or 0.30mm grades.

Compliance: B23R085 meets or exceeds IEC 60404-8-7, GB/T 2521-2017, ASTM A876 (Type 1, High Permeability), and is widely accepted for IEEE C57.12.00 transformer designs.

Conclusion: Choose B23R085 0.23mm 0.85W/kg Grain-Oriented Silicon Steel Coil

 

B23R085 0.23mm 0.85W/kg Grain-Oriented Silicon Steel coil offers a unique combination of ultra-low core loss (≤0.85 W/kg), high magnetic induction (B8 ≥1.88 T), and a thin 0.23mm gauge that minimizes eddy currents. It is the Hi-B solution for transformer manufacturers who need to meet the highest efficiency standards (DOE, Ecodesign, IE5) while maintaining competitive material costs.

 

Whether you are producing distribution transformers, power transformers, or specialized reactors, GNEE has the stock, slitting capacity, and global logistics to deliver prime B23R085 silicon steel coils tailored to your exact width, coating, and packaging requirements.

 

📩 Ready to reduce your transformer core losses?
Contact GNEE today for a competitive quotation, free material sample (up to 10 kg), or a technical datasheet package. Simply tell us your required width, annual volume, and target core loss - and we will respond within 24 hours with a solution that fits your budget and schedule.

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What is grain-oriented silicon steel?

Grain-oriented electrical steels (GOES) are silicon steels and are used in power distribution networks as transformer cores. The main magnetic properties required are high permeability and low core loss. Hysteresis losses and eddy current loses are both part of the core loss.

 

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.