| Control | Range | Typical working spec | Notes |
|---|---|---|---|
| Product type | Sintered · injection-molded · assemblies | Sintered NdFeB | Assemblies include Halbach arrays, radial rings, linear tracks. |
| Series | F (HREE-free) · N (conventional) · D (GBD) | D-Series | F-Series = no MOFCOM licence. D-Series = GBD (factory-verified case: 75% less Dy). |
| Grade | N30 to N58 | N42SH | Full N / M / H / SH / SHT / UH / UHT / EH / EHT / AH classes. |
| Br (remanence) | 1.08 – 1.47 T | 1.28 T (N42) | N56 at 1.51T available on request. N33AH 1.12T for 230°C. |
| Max temp | 80 – 230 °C | 150 °C (SH) | N (80) · M (100) · H (120) · SH (150) · UH (180) · EH (200) · AH (230). |
| Shape | Block · disc · ring · arc · countersunk · Halbach · custom | Radial multipole ring | Per drawing / STEP. Arc up to 180°. |
| OD range | 1.0 – 250 mm (arcs) | 40 – 120 mm | Rings 3–120 · Discs 1–80 · Blocks L 1–100 × W 1–80 × H 1–50. |
| Tolerance · ≤ 10 mm | ±0.03 (wire cut) · ±0.05 (grind) | ±0.05 mm | Per GB/T 13012. |
| Tolerance · 20–50 mm | ±0.08 – 0.13 mm | ±0.10 mm | Tighter on specific geometries on request. |
| Deviation angle | ±3° (post-mag, 100% inspected) | ±3° | Industry standard ±5°. 70–80 % pass rate to achieve ±3°. |
| Poles | 2 · 4 · 8 · 10 · 12 (radial multipole) | 10 / 12 | +30 % surface gauss vs tile assemblies. |
| Coatings | Ni · NiCuNi · Zn · Black Epoxy · NiCu+Epoxy · phosphate · passivation | NiCuNi 15–30 µm | Black Epoxy 96 h salt spray. Ni 72 h. NiCuNi 24 h. |
| HAST durability | < 1 mg/cm² @ 132 °C · 3 atm · 100 % RH · 60 d | L-35SH-T | L- prefix = low-weight-loss formulation. Grade-specific. |
| Lead time | ~4 weeks (no MOFCOM) · 3–4 mo with MOFCOM | ~4 weeks | F-Series fastest. MOFCOM-required programs need 3–4 months. |
| MOQ | Samples to production | Samples OK | No unit floor disqualifies a program. |
| QC | Cpk · Br · Hcj · flux · adhesion · coating · HAST | PPAP L3 (13 docs) | GB/T 2828.1-2003 sampling. Per-batch BH curve. |
| Export | MOFCOM in-house (N / D) · none required (F) | Handled | Ho-substituted grades licence-free during suspension (to Nov 2026). |
| Pricing | 6–12 month fixed-price contracts | Locked | Enabled by three decades of upstream supply relationships. |
Custom NdFeB magnets.From drawing to delivery.
Sintered NdFeB across three series: F, HREE-free with no MOFCOM licence needed, N, conventional, and D, GBD with a factory-verified case using 75 % less Dy. Injection-molded magnets and custom assemblies include Halbach arrays and radial multipole rings. Work is engineered and quality-controlled by Mainrich across a four-site production network Mainrich holds equity stakes in.

Everything a buyer asks before an RFQ.
A screenshot-friendly engineering ledger covering material series, grade, temperature, geometry, tolerance, coating, inspection, export path, and commercial terms. Last reviewed April 2026.
The typical working spec is the common point inside the stated range, not the manufacturing limit. Drawing review determines the final combination of grade, geometry, tolerance, coating, and inspection.
Which NdFeB grade families trigger licensing.
Br, temperature class, coercivity route, HREE exposure, and current MOFCOM status in one view. Green N/M/H grades are the low-friction export path; SH and above need chemistry review before quoting.

Grade-to-application, from production records.
Real assignments from Mainrich automotive programs, organized as a working reference rather than a universal grade recommendation.
| Application | Component | Typical grades |
|---|---|---|
| EV drive motors | BEV / HEV traction | 38SH · 35UH · 38UH · 40EH |
| EPS motors | Electric power steering | 45H · 48H · 38SH · 40SH · 42SH · 48SH |
| Active suspension | Electromagnetic dampers | 42SH |
| Pump motors | Thermal mgmt · coolant | 33UH · 35UH |
| Starter motor | ICE start | 38UH |
| Generator | On-board | 38UH |
| ABS sensor | Anti-lock braking | 44H · 42SH |
| CAM sensor | Camshaft position | 42SH · 33EH |
| Gearbox | Position sensing | 38UH · 35EH |
| Ignition coil | ICE | 30UH · 33UH · 35UH · 33EH |
| Body · comfort | Window · seat · sunroof · liftgate | 35M · 38H |
| In-cabin audio | Speakers | 38H · 40H |
Radial multipole rings for joint motors.
A full humanoid robot contains 20–50+ actuator motors. Hip, knee, and shoulder joints use radial multi-pole sintered NdFeB rings, typically 40–120 mm OD with 8–12 poles.
Continuous operating temperature under sustained load routinely reaches 100–130 °C, which puts N42SH as the working floor and N45SH / N48SH as the standard. In the factory-verified GBD case, the D-Series route held flux, with no Br loss, at 75 % less Dy. Mainrich radial multipole rings deliver +30 % surface gauss versus tile assemblies.
| Series | D (GBD) |
|---|---|
| Grade | N45UH |
| Shape | Radial multipole ring |
| OD | 40 – 120 mm |
| Poles | 10 / 12 |
| Tolerance | ±0.05 mm |
| Max temp | 180 °C |
| Coating | NiCuNi 15–30 µm |
| Lead | ~5 weeks |
Same FAQ, same answers, collected in one place.
Send the drawing, operating temperature, coating requirement, and destination. Mainrich separates manufacturing lead time from MOFCOM licensing so the quote shows the real schedule.
What's your real lead time?~4 weeks · 3–4 mo/MOFCOM
When is GBD (D-Series) worth it vs conventional high-Dy?≥ 150 °C
Do I need an export licence for my shipment?Depends on series
How tight can you actually hold?Cpk 2.95
What coating for corrosive environments?Black Epoxy
Can you run small quantities?Yes
Send us your drawing.
PDF or STEP. An engineer responds within 1 business day with candidate grades and FEM review where useful. Pricing follows within 2 business days with tolerances stated explicitly.
