1. Product Overview

NdFeB ring magnets are high-performance permanent magnets in a hollow cylindrical (ring) shape, characterized by excellent maximum energy product (BHmax) and stable magnetic output. They are widely used in applications requiring axial or radial magnetic fields, such as rotary sensors, motors, and magnetic bearings. Dimensions, magnetization direction, and surface coatings can be customized to meet specific customer requirements.

 2. Technical Parameters

- Product Name: NdFeB Ring Magnets

- Magnet Grade: N50  (Br ≥ 14.8 KGs, Hcj ≥ 12 KOe)

- Dimensions: D15 x d8 x H3

- Tolerances: ±0.05 mm in length, width, and thickness

- Working Temperature: ≤ 80°C (custom high-temperature versions available)

- Density: ≥ 7.5 g/cm³

- Surface Magnetic Field: 2800-3000 Gauss (measured with TM-801 Gauss meter, Japan)

- Magnetic Flux: 2.8-2.9 mWb (measured with fluxmeter)

3. Manufacturing Process

The product is manufactured through the following key processes:

Wire Cutting: Uses molybdenum/copper wire cutting equipment to achieve ±0.02mm precision for small-batch custom rings.

Centerless Grinding: Refines inner and outer diameters to ensure roundness (±0.05mm tolerance).

Double-Disc Grinding: Controls thickness and parallelism.

4. Surface Treatment & Coating Technologies

Epoxy Coating:
Offers additional protection against chemical corrosion and water ingress. Particularly suitable for high-humidity environments.

Ni-Cu-Ni Plating:
Standard triple-layer electroplating that provides both aesthetic appeal and corrosion resistance. Ideal for industrial and electronic applications.

5. Appearance & Dimensional Inspection Standards

Manual Inspection with Caliper/Micrometer:
Ensures each product meets the specified dimensions and tolerance requirements.

Visual Inspection:
Under standard lighting conditions to detect cracks, defects, or contamination.

2D Vision Measurement System:
High-resolution non-contact imaging used to inspect complex or irregular shapes for precision.

CCD Automatic Sorting System:
Uses high-speed image recognition to automatically inspect and sort magnets by appearance and size, enhancing efficiency and reducing manual error.

Magnetic Flux Consistency Test:
Performed using professional instruments to ensure uniform magnetic properties across different batches.

6. Reliability Testing

Shock and Vibration Test:
Simulates transportation and operational shocks to verify product robustness.

High-Temperature Demagnetization Test:
Verifies magnetic stability at elevated temperatures to ensure long-term performance.

Damp Heat Test:
Tests resistance to humidity and corrosion under high-moisture conditions.

7. Packaging & Transportation

Defective Product Removal:
Rejects magnets that do not meet visual or dimensional standards.

Magnetization & Alignment:
Ensures uniform magnetization and organized packaging based on customer specifications.

Vacuum Packaging:
Protects against moisture and magnetic interference.

Outer Packaging:
Uses shock-proof, moisture-resistant, and anti-magnetic shielding cartons for safe transport.

8. Application Fields

Brushless Motors:
Acts as a rotor component to deliver stable magnetic field drive.

Rotary Sensors:
Paired with Hall elements for precise position detection.

Magnetic Suspension Systems:
Includes magnetic bearings and magnetic couplings.

Consumer Electronics:
Used in speaker components, audio magnetic circuits, and headphones.

Medical Devices:
Applies to magnetic fixtures and magnetically guided positioning systems.

9. Usage Precautions

Handling:
NdFeB magnets are hard yet brittle. Avoid dropping, impact, or edge chipping during handling

Safe Use:
Due to strong magnetic force, do not bend or pry magnets apart. Use sliding motion to avoid pinching.

Correct Installation:
Determine magnetic polarity based on magnet shape and install properly to ensure device functionality.

Storage:
Avoid high temperature, humidity, or exposure to strong acids or alkalis. Store in dry, corrosion-resistant conditions.

Magnetic Isolation:
Keep away from sensitive equipment such as hard drives, IC cards, and pacemakers due to strong magnetic interference.

10. Customization & Services

Customizable sizes, shapes, and coatings (layers, thickness, color)

Magnetic polarity and field strength can be tailored to application needs

Laser engraving of logos or serial numbers available

Custom packaging and pull-force testing services for specific requirements

11.Company Introduction

Dongguan Jinconn New Materials Holdings Co., Ltd specializes in the research, development, production, and sales of high-performance magnetic materials. Upholding the core philosophy of "Technology as the foundation, Quality as the soul," the company is committed to becoming a global leader in magnetic material solutions. Its products are widely used in cutting-edge fields such as new energy vehicles, intelligent manufacturing, electronic communications, automation equipment, and medical devices, earning strong recognition and trust from clients both domestically and internationally.

If you require samples, technical datasheets, or certifications such as MSDS, RoHS, ISO 9001, QC080000, IATF 16949, ISO 14001, or ISO 27001, our sales engineers are ready to assist you.