Ring NdFeB Magnet

1. Product Overview

Ring-shaped NdFeB magnets deliver exceptional magnetic performance and superior demagnetization resistance. Their annular structure creates a closed magnetic circuit, ensuring uniform and concentrated field distribution for specialized magnetic path designs. Compared to other high-performance permanent magnets, they offer greater cost-effectiveness due to abundant raw material availability.  

 2. Technical Parameters:   

- Product Name: Ring-shaped NdFeB Permanent Magnet  

- Magnet Grade: N48 (Br ≥14.3 kGs, Hcj ≥10.8 kOe)  

- Dimensions:  24mm ×  21mm × H 4mm  

- Dimensional Tolerance: L±0.05mm, W±0.05mm, T±0.05mm  

- Operating Temperature: ≤80°C (High-temp versions customizable)  

- Density: ≥7.5 g/cm³  

- Surface Magnetic Field**: 2,400 Gs  

-Magentic Field : 2.2 mWb  (Fluxmeter-tested)  

3. Manufacturing Process:

Special-Shaped Cutting: Performed using dedicated non-standard wire-cutting equipment for non-square/non-circular geometric machining.

Grinding & Shaping: Used for complex structures and high-precision contour finishing to ensure dimensional and geometric tolerances.

Demagnetization Treatment: Initial demagnetization followed by precise magnetization to prevent magnetic deviation after assembly.

 4. Surface Treatment & Plating 

Common coatings: Nickel (Ni), Zinc (Zn), Epoxy, or Parylene to prevent corrosion.

5. Appearance & Dimensional Inspection  

- Visual inspection: 800-1,200 Lux illumination, 20-750px distance  

- 2D optical measurement: For irregular/non-standard structures  

-CCD sorting machine: Automated full inspection (appearance/dimensions)  

6. Reliability Testing  

6.1 Magnetic Performance

- Field strength mapping (Gauss meter verification)  

- Stability testing under thermal/humidity aging  

6.2 Physical Properties  

- Hardness test (Rockwell/Vickers hardness testers)  

- Density measurement (structural uniformity)  

- Dimensional accuracy (micrometer/caliper)  

7. Packaging Process  

Reject appearance/dimensional defects  

Magnetized conforming products → Aligned in uniform orientation  

Custom quantitation/labeling per box  

Individual vacuum sealing  

8. Application Fields  

- Electronics: Miniature speakers/sensors (earphones, field detection)  

-Toys: Magnetic puzzles/educational kits (interactive assembly)  

- Jewelry: Magnetic clasps (necklaces/bracelets)  

- Research: Microscopic field sources (cell manipulation, material studies)  

- Industry: Micro-relays, magnetic fixtures  

9. Usage Precautions

- Mechanical: Impact protection during transit; No press-fit assembly  

- EM Safety: Keep >750px from pacemakers/sensitive devices  

- Performance: Never exceed Curie temperature; Avoid reverse magnetization  

10. Customization & Services

- Dimensions/shapes/coatings (layers, thickness, color)  

- Polarity/magnetic strength customization  

- Laser marking (logos/ serial numbers)  

- Application-specific encapsulation & pull-force testing  

11.Company Introduction

Dongguan Jinkun New Material Co., Ltd. is an innovative leader in the field of high-performance magnetic materials, specializing in the full-chain layout of R&D, production, and sales of magnetic materials. Its core products are widely used in high-tech sectors such as new energy vehicle drive systems, precision components for intelligent manufacturing, 5G communication equipment, industrial automation control modules, and high-end medical devices. With outstanding performance and stable quality, the company has earned the trust of high-end clients both domestically and internationally.

- Patent

Request samples, datasheets (MSDS/RoHS), or certifications (ISO9001, IATF16949, etc.) from sales engineers.