Neodymium Ring Magnets - Custom Magnetic Solutions | Fullzen
Fullzen is a professional manufacturer of custom neodymium ring magnets, offering a full range of grades from N35 to N54 (including H/SH/UH high-temperature grades) with precise tolerances of +/-0.05mm. We serve 100+ global industrial customers in electronics, automotive, medical and new energy sectors, with flexible MOQs starting at 1,000 pieces and free sample support for qualified projects.
Neodymium Ring Magnets – Custom Magnetic Solutions for Motors, Sensors and Industrial Equipment
Fullzen Technology manufactures custom neodymium ring magnets for demanding industrial applications including electric motors, rotary encoders, magnetic couplings, medical devices and automation systems.
Unlike standard catalog magnets, our ring magnets can be customized in:
With production tolerances as tight as ±0.05mm and grades ranging from N35 to N54, Fullzen supports OEM and engineering teams worldwide with reliable magnetic solutions.
Why Engineers Choose Neodymium Ring Magnets
The ring shape is one of the most versatile permanent magnet geometries.
Compared with solid disc magnets, ring magnets provide:
✅ Direct shaft mounting
✅ Lower rotating inertia
✅ Better magnetic flux distribution
✅ Easier assembly in motors
✅ Multi-pole magnetization capability
In our experience serving motor manufacturers and sensor companies, more than 60% of custom ring magnet projects are used in rotational applications where shaft integration is critical.
What Are Neodymium Ring Magnets?
Neodymium ring magnets are high-strength rare earth magnets featuring a hollow circular design that enables direct shaft mounting and focused magnetic field patterns. Made from sintered NdFeB material, they offer the highest magnetic energy product of any permanent magnet type.
Fullzen manufactures custom neodymium ring magnets from 2mm to 200mm outer diameter with precise tolerances, serving motor, sensor, coupling, and medical applications worldwide.
Why Choose Us as Your Neodymium Ring Magnets Manufacturer?
As a professional magnet manufacturer with our own factory in China and over 10 years of production experience, we offer OEM & ODM services, providing factory-direct pricing and stable supply.
Precision Engineering – Tolerances as tight as ±0.05mm, 100% dimensional inspection on every batch.
Full Grade Range – N35 to N54, plus H/SH/UH/EH high-temperature grades for all applications.
Multiple Coatings – Nickel, zinc, epoxy, gold, parylene coatings for corrosion resistance in any environment.
End-to-End Manufacturing – In-house melting, pressing, sintering, machining, coating, and magnetization.
Certified Quality – ISO 9001 and IATF 16949 certified, REACH and RoHS compliant, <0.1% defect rate.
Technical Support – Expert engineering team for design optimization and rapid prototyping in 7 days.
Magnetization Directions
Magnetization direction determines how the magnetic field is oriented, directly impacting performance in your application. Choosing the right pattern is critical for optimal force and efficiency.
Selecting the correct magnetization direction is often more important than choosing the highest grade.
Axial Magnetization
North and South poles are located on opposite flat faces.
Best for:Holding systems、Magnetic fixtures、Mounting applications、Closures
Advantages:Highest pull force、Lowest cost、Simplest production
Radial Magnetization
North and South poles are positioned on the outer and inner diameters.
Best for:Electric motors、Magnetic couplings、Rotary devices
Advantages:Optimized rotational magnetic field、Improved motor efficiency、Better torque generation
Multi-Pole Magnetization
Alternating north and south poles around the circumference.
Commonly used in:Encoders、Hall sensors、Servo systems、BLDC motors
Neodymium Ring Magnet Grades & Performance
Magnet grade indicates the maximum energy product (MGOe), which directly correlates to holding force and magnetic strength. Higher grades deliver more force in smaller sizes but come at a premium and may have lower temperature resistance.
| Grade | Max Energy (MGOe) | Remanence (kG) | Max Temp (°C) | Typical Applications |
| N35 | 35 | 12.1 | 80 | General holding, sensors |
| N38 | 38 | 12.6 | 80 | Standard motors |
| N42 | 42 | 13.2 | 80 | High-performance motors |
| N45 | 45 | 13.5 | 80 | Precision instruments |
| N48 | 48 | 13.8 | 80 | High-strength apps |
| N52 | 52 | 14.5 | 80 | Maximum strength, miniaturized |
| N35H | 35 | 12.1 | 120 | Automotive motors |
| N42SH | 42 | 13.2 | 150 | Industrial high-temp |
| N38UH | 38 | 12.6 | 180 | Aerospace, extreme env |
| N30EH | 30 | 11.8 | 200 | High-temp aerospace |
Protective Coatings
The right coating is critical to magnet longevity — neodymium is highly susceptible to corrosion and oxidation. Choosing the wrong coating leads to premature failure, performance degradation, and contamination risks.
| Coating | Corrosion Resistance | Color | Typical Applications |
| Ni-Cu-Ni Nickel | Good (indoor) | Silver | General industrial, electronics |
| Zinc | Moderate | Silver-gray | Low-cost applications |
| Epoxy | Excellent (outdoor/humid) | Black/Gray | Marine, outdoor equipment |
| Black Epoxy | Excellent | Black | Outdoor, aesthetic uses |
| Gold | Excellent (biocompatible) | Gold | Medical devices, implants |
| Parylene | Superior (chemical) | Transparent | Medical, harsh chemicals |
Industrial Applications
Neodymium ring magnets are versatile components used across every industry requiring compact, high-strength magnetic fields. Their hollow design enables unique mounting and field-shaping capabilities that solid disc magnets cannot match.
✅ Electric Motors & Generators
Essential in BLDC motors, stepper motors, servo motors, and generators. Hollow design allows direct shaft mounting for efficient torque transmission and improved motor efficiency.
✅Magnetic Couplings & Separators
Non-contact torque transmission in pumps, mixers, and sealed systems. Eliminates mechanical seals, reducing maintenance and preventing leaks in chemical and food processing equipment.
✅Sensors & Encoders
Diametrically and multi-pole magnetized rings for position sensors, rotary encoders, speed sensors, and proximity sensors in automotive and industrial automation.
✅Medical Devices
MRI components, medical pumps, surgical equipment, and dental devices. Biocompatible gold and parylene coatings available for FDA-compliant medical applications.
✅Automotive Systems
EV motors, power steering, fuel injectors, door latches, and sensor rings. High-temperature H/SH/UH grades ensure reliable under-hood performance.
✅New Energy & Aerospace
Wind turbine generators, solar tracking systems, aerospace components, and satellite equipment requiring high performance and long-term reliability in extreme environments.
Manufacturing Process & Quality
Quality Commitment
✓ ISO 9001:2015 and IATF 16949 certified
✓ 100% dimensional inspection on critical dimensions
✓ Magnetic flux testing for performance consistency
✓ Salt spray testing for corrosion resistance
✓ REACH and RoHS compliant
✓ PPAP / IMDS documentation available on request
How to Choose the Right Ring Magnet
Selecting the optimal ring magnet involves balancing performance requirements, cost constraints, and environmental operating conditions. Use this guide to narrow down your options, or contact our engineering team for personalized recommendations.
1. Strength Requirements
Start with the magnetic force or flux density needed for your application. Higher grades (N42, N48, N52) provide stronger fields in smaller sizes but cost more.
2. Operating Temperature
Standard N-grade: up to 80°C | H-grade: up to 120°C | SH-grade: up to 150°C | UH-grade: up to 180°C | EH-grade: up to 200°C
3. Magnetization Direction
Axial for holding/stacking | Radial for motors/couplings | Multi-pole for encoders/sensors | Custom patterns available
4. Protective Coating
Nickel for indoor/dry environments | Epoxy for outdoor/humid | Parylene for chemical/submerged | Gold for medical/biocompatible
5. Dimensional Specs & Tolerance
Define OD, ID, and thickness requirements. Tighter tolerances (±0.02mm available) increase cost; standard ±0.05mm for most applications.
6. Quantity & Budget
Prototype: 1,000-5,000 pcs (higher per-unit cost) | Production: 10,000+ pcs (economies of scale, better pricing)
�� Tip: Unsure which configuration is right for your project? Send Fullzen your application requirements and our engineers will recommend the optimal neodymium ring magnet specification.
Pull Force Reference
Pull force is one of the most commonly requested specifications, particularly for holding and mounting applications. It represents the maximum force required to pull a magnet away from a thick steel surface under ideal conditions.
| OD x ID x Thickness | N35 Pull Force | N42 Pull Force | N52 Pull Force |
| 10mm x 5mm x 2mm | 0.8 kg (1.8 lbs) | 1.0 kg (2.2 lbs) | 1.2 kg (2.6 lbs) |
| 15mm x 8mm x 3mm | 2.5 kg (5.5 lbs) | 3.1 kg (6.8 lbs) | 3.8 kg (8.4 lbs) |
| 20mm x 10mm x 5mm | 6.5 kg (14.3 lbs) | 8.0 kg (17.6 lbs) | 10.0 kg (22.0 lbs) |
| 30mm x 15mm x 5mm | 12.0 kg (26.5 lbs) | 14.8 kg (32.6 lbs) | 18.5 kg (40.8 lbs) |
| 40mm x 20mm x 10mm | 35.0 kg (77.2 lbs) | 43.0 kg (94.8 lbs) | 54.0 kg (119.0 lbs) |
Notes: Tested on 10mm thick steel plate, full surface contact. Actual force varies with air gap, surface condition, and steel grade.
�� Fullzen can calculate custom pull force data for your specific application and size requirements.
What we can offer you…
Safety & Handling
Pinching Hazard
Neodymium magnets are extremely strong relative to their size. Large magnets can pinch fingers or cause serious injury. Always handle with care and keep away from children.
⚠ Pacemakers & Medical Devices
Strong magnetic fields can interfere with pacemakers, ICDs, and other implanted medical devices. Keep magnets at least 30cm away from anyone with such devices.
⚠ Swallowing Hazard
Small magnets pose a serious choking hazard. If swallowed, magnets can attract across intestinal walls causing severe injury or death. Seek immediate medical attention.
⚠ Eye Protection
Wear safety glasses when handling large or powerful magnets. Magnets can snap together with surprising force, and chipped material can fly at high speed.
⚠ Demagnetization Risk
Avoid exposing magnets to temperatures above their rating. Do not strike or shock magnets physically, as impact can reduce magnetic performance and cause chipping.
Couldn’t find what you looking for?
Generally, there are stocks of common neodymium magnets or raw materials in our warehouse. But if you have special demand, we also provide customization service. We also accept OEM/ODM.
FAQs about Neodymium Ring Magnet
Flexible MOQs starting from 1,000 pieces for standard configurations. Custom sizes may have higher minimums depending on complexity. Stock items available for prototyping.
Yes, we manufacture exactly to customer drawings and specifications. Our engineering team reviews all drawings for manufacturability before production and provides DFM feedback.
1) Drawing/specs (OD, ID, thickness, grade, coating, tolerance)
2) Quantity
3) Magnetization direction
4) Application and operating environment
5) Any special requirements
Full range: N35, N38, N40, N42, N45, N48, N50, N52 plus temperature-stabilized N35H, N42H, N42SH, N38UH, N30EH. Custom grade development available.
Custom orders: 20-25 working days from drawing approval. Stock items: 3-5 working days. Rush production (10-15 days) available for urgent projects with expedite fee.
Yes, with appropriate grade selection. Standard N-grade magnets work up to 80°C, while high-temperature grades (H/SH/UH/EH) can operate up to 200°C without demagnetization.
Choose axial magnetization for holding, stacking, and flat-surface applications. Choose radial/diametrical for motors, couplings, and applications involving rotation around a shaft.
Uncoated neodymium corrodes quickly underwater. With proper epoxy, parylene, or plastic encapsulation, they can be used in submerged and marine applications.
N52 has approximately 48% higher magnetic energy product than N35 of the same size. N52 costs more and may be more susceptible to demagnetization at high temperatures.
Yes, including multi-pole configurations, Halbach arrays, and other specialized patterns. Our engineering team designs custom magnetization patterns to meet your specific requirements.
Yes, samples available within 5-7 working days for standard sizes, 10-15 days for custom sizes. For qualified projects, samples may be free (you cover shipping).
ISO 9001:2015 and IATF 16949 certified manufacturing. All products are REACH and RoHS compliant. PPAP, IMDS, and COC documentation available on request.
