NdFeB Ring Magnet Rare Earth Magnet

NdFeB Ring Magnets offer the perfect combination of a central through-hole and high-energy rare earth performance, enabling secure shaft or screw mounting without compromising magnetic output. These sintered neodymium-iron-boron annular magnets are engineered for applications where both holding force and mechanical fixation are required, such as magnetic couplings, rotary encoders, brushless DC motor rotors, and pneumatic valves. Our rings are available in grades N35 to N52 and high-temperature series (SH, UH, EH), with precision ground ID/OD surfaces and tight concentricity. Standard Ni-Cu-Ni triple plating provides corrosion resistance, while epoxy or gold coatings are available for specialized environments. With full in-house production from raw material to finished ring, we guarantee consistent magnetic flux, dimensional accuracy, and fast delivery for OEM and industrial buyers worldwide.

Why Design Engineers Prefer Our NdFeB Ring Magnets

Shaft-Ready Geometry

The central hole allows direct mounting on bolts, pins, or motor shafts. No need for complex adhesives or external housings. Our ID tolerances of H7 or custom fits ensure slip-fit or press-fit as required.

Wide Grade & Coating Range

Choose from N35 (economy) to N52 (maximum energy). High-temp grades: N42SH (150°C), N40UH (180°C), N35EH (200°C). Coatings: Ni-Cu-Ni (standard), epoxy (insulation), gold (medical), or rubber (impact protection).

Precision Magnetization Options

Axial (through thickness), diametrical (across diameter), or multi-pole patterns (2 to 48 poles) for encoder and sensor applications. Polarity accuracy ±1° for consistent Hall switching.

Neodymium magnets can maintain dimensional accuracy within ±0.05mm through advanced precision machining techniques including surface grinding and CNC cutting processes. This tight tolerance control ensures consistent performance in applications requiring precise magnetic field distribution and mechanical fit.

Our factory controls every production step: vacuum induction melting of virgin rare earths (no recycled scrap), jet milling, axial/diametrical pressing, sintering, solution heat treatment, precision grinding, automated Ni-Cu-Ni electroplating, and multi-pole magnetization. Each ring is inspected for magnetic flux (Helmholtz coil), ID/OD concentricity (CMM), and coating thickness (XRF). Salt spray testing validates corrosion resistance per ASTM B117. We provide full material traceability and test reports with every shipment. Our IATF 16949 and ISO 9001 systems ensure consistent quality for automotive, medical, and industrial OEMs.

Each ring is individually foam-padded in 8-cell inner boxes to prevent edge chipping. Outer cartons are reinforced for air or sea freight. Standard sizes: 5-7 days lead time. Custom rings: 12-15 days after drawing approval. Free samples available for qualified projects. Express shipping via DHL/FedEx or economical LCL/FCL container.