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Custom NdFeB / engineering desk

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.

N30 to N58Grade range
±0.03 mmWire-cut tolerance
±3°Deviation angle
~4 weeksNo-MOFCOM lead
Samples OKProgram entry
IATF 16949Certified plant route
GB/T 13012 · IEC 60404-5Standards
PPAP L3Quality evidence
Real product rangeReal NdFeB product range including rings, arc segments, discs, blocks, and finished magnetic parts
Custom magnet reference / real productsSintered rings, arc segments, discs, blocks, and finished magnetic parts.
Automotive IATF 16949 work runs through the network's certified plant ·  100 % post-magnetization inspection where specified ·  30 years of upstream supply relationships ·  response within 1 business day
01 / CAPABILITY MATRIX

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.

Custom NdFeB control ledgerRange / working spec / notes
ControlRangeTypical working specNotes
Product typeSintered · injection-molded · assembliesSintered NdFeBAssemblies include Halbach arrays, radial rings, linear tracks.
SeriesF (HREE-free) · N (conventional) · D (GBD)D-SeriesF-Series = no MOFCOM licence. D-Series = GBD (factory-verified case: 75% less Dy).
GradeN30 to N58N42SHFull N / M / H / SH / SHT / UH / UHT / EH / EHT / AH classes.
Br (remanence)1.08 – 1.47 T1.28 T (N42)N56 at 1.51T available on request. N33AH 1.12T for 230°C.
Max temp80 – 230 °C150 °C (SH)N (80) · M (100) · H (120) · SH (150) · UH (180) · EH (200) · AH (230).
ShapeBlock · disc · ring · arc · countersunk · Halbach · customRadial multipole ringPer drawing / STEP. Arc up to 180°.
OD range1.0 – 250 mm (arcs)40 – 120 mmRings 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 mmPer GB/T 13012.
Tolerance · 20–50 mm±0.08 – 0.13 mm±0.10 mmTighter on specific geometries on request.
Deviation angle±3° (post-mag, 100% inspected)±3°Industry standard ±5°. 70–80 % pass rate to achieve ±3°.
Poles2 · 4 · 8 · 10 · 12 (radial multipole)10 / 12+30 % surface gauss vs tile assemblies.
CoatingsNi · NiCuNi · Zn · Black Epoxy · NiCu+Epoxy · phosphate · passivationNiCuNi 15–30 µmBlack Epoxy 96 h salt spray. Ni 72 h. NiCuNi 24 h.
HAST durability< 1 mg/cm² @ 132 °C · 3 atm · 100 % RH · 60 dL-35SH-TL- prefix = low-weight-loss formulation. Grade-specific.
Lead time~4 weeks (no MOFCOM) · 3–4 mo with MOFCOM~4 weeksF-Series fastest. MOFCOM-required programs need 3–4 months.
MOQSamples to productionSamples OKNo unit floor disqualifies a program.
QCCpk · Br · Hcj · flux · adhesion · coating · HASTPPAP L3 (13 docs)GB/T 2828.1-2003 sampling. Per-batch BH curve.
ExportMOFCOM in-house (N / D) · none required (F)HandledHo-substituted grades licence-free during suspension (to Nov 2026).
Pricing6–12 month fixed-price contractsLockedEnabled by three decades of upstream supply relationships.
Read the working spec as the common point.

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.

MOFCOM grade map

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.

Export control guide
Magnetic property distribution chart showing NdFeB grade families by maximum working temperature, intrinsic coercivity, HREE requirement, Ho exposure, and MOFCOM licensing status.
Use this as an RFQ planning map, then confirm the final export path with composition testing, destination, and current MOFCOM guidance.
02 / AUTOMOTIVE REFERENCE

Grade-to-application, from production records.

Real assignments from Mainrich automotive programs, organized as a working reference rather than a universal grade recommendation.

Automotive application ledgerProgram records
ApplicationComponentTypical grades
EV drive motorsBEV / HEV traction38SH · 35UH · 38UH · 40EH
EPS motorsElectric power steering45H · 48H · 38SH · 40SH · 42SH · 48SH
Active suspensionElectromagnetic dampers42SH
Pump motorsThermal mgmt · coolant33UH · 35UH
Starter motorICE start38UH
GeneratorOn-board38UH
ABS sensorAnti-lock braking44H · 42SH
CAM sensorCamshaft position42SH · 33EH
GearboxPosition sensing38UH · 35EH
Ignition coilICE30UH · 33UH · 35UH · 33EH
Body · comfortWindow · seat · sunroof · liftgate35M · 38H
In-cabin audioSpeakers38H · 40H
03 / HUMANOID ROBOTICS

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.

Design for the sustained thermal envelope.

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.

Typical joint-motor programWorking reference
SeriesD (GBD)
GradeN45UH
ShapeRadial multipole ring
OD40 – 120 mm
Poles10 / 12
Tolerance±0.05 mm
Max temp180 °C
CoatingNiCuNi 15–30 µm
Lead~5 weeks
04 / RFQ NOTES

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
F-Series (no MOFCOM): ~4 weeks. Pure manufacturing cycle. If the shipment requires MOFCOM export licensing, plan for roughly 3–4 months end-to-end. We handle the paperwork in-house, but we do not treat licensing as a 4–6 week path.
When is GBD (D-Series) worth it vs conventional high-Dy?≥ 150 °C
Typically best for SH / UH / EH equivalents. Verified example: N45H upgraded to N45UH with 0.35 % Tb surface coating: Hcj +50 % (17.67 to 26.55 kOe), no Br loss, 75 % less Dy.
Do I need an export licence for my shipment?Depends on series
N / D series (HREE-containing): MOFCOM licence required, handled in-house, no third-party queue. F-Series: no licence (no Dy / Tb / Ho / Gd).
How tight can you actually hold?Cpk 2.95
Dimensional Cpk of 2.95 on OD across production runs (benchmark > 1.33 = capable). Br batch variation ±0.37 % on N45SH. Inter-batch flux variation < 5 %. Full PPAP L3 report available.
What coating for corrosive environments?Black Epoxy
Worst-case corrosion: Ni-Cu + Epoxy or Black Epoxy, 96 h salt spray. Default NiCuNi 24 h at 15–30 µm. Ni 72 h at 10–20 µm. Zn budget alternative.
Can you run small quantities?Yes
Samples and low-volume production run on the same tooling. No unit floor disqualifies a program.
Request for quote

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.