M36/M43-class non-oriented electrical steel — quick answer
Quick answer: M36 and M43 are AISI loss classes for 0.50 mm non-oriented electrical steel. The Baosteel equivalents are 50WW800 (enterprise grade, max 5.50 W/kg P1.5/50) and B50A800 (GB/T 2521.1 grade, max 5.80 W/kg P1.5/50), also written 50W800 under GB/T 2521.1-2016. In EN 10106 designation these map to the M800-50A class; the Japanese class equivalents are JIS 50A800 / 50A1000. This is the cost-efficiency grade: home appliances, refrigeration compressors, fans, pumps and small motors with moderate duty cycles.
How to read the grade designations
Electrical steel grades encode thickness and core loss. In 50WW800: 50 = 0.50 mm nominal thickness, WW = conventional non-oriented (WH = high-efficiency), 800 = nominal loss 8.00 W/kg at 1.5 T / 50 Hz. In B50A800: B = Baosteel Q/BQB designation, 50 = 0.50 mm, A = conventional non-oriented, 800 = same nominal loss. In EN M800-50A: M800 = 8.00 W/kg loss class, 50 = 0.50 mm, A = insulation coating class. AISI M36/M43 belong to the same loss band but are specified in W/lb at 1.5 T / 60 Hz, so the numbers are not directly comparable.
Magnetic properties (per Baosteel Q/BQB 480-2023)
| Grade | Nominal thickness (mm) | Max core loss P1.5/50 (W/kg) | Min polarization J5000 (T) | Min stacking factor | Typical density (kg/dm³) |
|---|---|---|---|---|---|
| B50A700 / 50WW700 | 0.50 | 4.70 | 1.70 | 0.97 | 7.80 |
| 50WW800 | 0.50 | 5.50 | 1.71 | 0.97 | 7.80 |
| B50A800 | 0.50 | 5.80 | 1.71 | 0.97 | 7.80 |
| 50WW1000 | 0.50 | 6.00 | 1.74 | 0.97 | 7.85 |
| B50A1000 | 0.50 | 6.00 | 1.74 | 0.97 | 7.85 |
Typical (non-guaranteed) values for 50WW800: P1.5/50 ≈ 5.25 W/kg, P1.0/50 ≈ 2.25 W/kg, P1.5/60 ≈ 6.50 W/kg. Full magnetic curves (J1000/J2500/J5000/J10000) ship with every quotation.
International grade equivalents
| China Q/BQB 480-2023 | China GB/T 2521.1 | EN 10106 | JIS C 2552 (class) | AISI (class) |
|---|---|---|---|---|
| B50A700 / 50WW700 | 50W700 | M700-50A | 50A700 | M43 |
| B50A800 / 50WW800 | 50W800 | M800-50A | 50A800 | M36 / M43 |
| B50A1000 / 50WW1000 | 50W1000 | M1000-50A | 50A1000 | M47 |
| B50A1300 | 50W1300 | M1300-50A | 50A1300 | — |
Class correspondence for reference only — test conditions differ between standards. Confirm the exact grade on the mill test certificate before ordering. See our full steel grade equivalent charts.
Typical applications
0.50 mm M36/M43-class NGO steel is the economy standard of the appliance industry: refrigeration and air-conditioning compressors, washing-machine and dishwasher motors, fans, range hoods, small pumps, power tools and ballasts. Where the motor runs intermittently or efficiency regulations are less strict (IE1/IE2 duty), the lower material cost of 50WW800 outweighs the higher core loss. Appliance OEMs in Latin America, the Middle East, Africa and Southeast Asia standardize on this class — it is also the grade most often tendered in bulk public procurement.
Supply form, coating and packaging
Supplied as slit coils: typical coil weight 2–6 t, inside diameter 508/510 mm, width on request (standard 900–1,250 mm). Standard insulation coatings include semi-organic C5/C6 and chrome-free types. Export packaging: moisture-proof paper + steel strapping, eye-to-sky or eye-to-wall container loading. Every coil ships with the original Baosteel mill test certificate (magnetic values per heat number). Full-container (FCL) and combined-container (LCL) shipments both available ex Shanghai.
Why Baosteel, why Baohui
Baosteel's 50WW800-class material offers appliance-industry buyers a rare combination: big-mill consistency at a mill-direct price, with full width coverage and stable coating quality for high-speed stamping lines. As a Baosteel channel partner, Baohui Steel quotes ex-mill or ex-warehouse with the original MTC, arranges slitting to your lamination width and handles export documentation end to end. Send your grade, thickness, width and quantity for a firm FOB Shanghai quotation within 24 hours — trial orders from one coil upward are welcome.
