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Neodymium Bar Magnets

Product Overview

High-Strength NdFeB Bar & Block Magnets | Custom Manufacturer & Wholesale Supplier

Manufactured from sintered Neodymium-Iron-Boron (NdFeB) alloy, our high-performance rare earth bar magnets deliver a maximum energy product ranging from 33 to 52 MGOe, providing concentrated magnetic flux in a compact rectangular profile.

Designed for global industrial distributors, sensor manufacturers, and OEM automation equipment builders, these magnets allow design engineers to drastically reduce component footprints compared to traditional ferrite alternatives while maintaining required holding force and air-gap flux density.

We produce both standard inventory sizes and build-to-print custom dimensions, supporting precise tolerances (down to +/- 0.05 mm), various magnetization vectors, and specialized protective platings. Backed by strict ISO9001 and IATF16949 quality management systems, all products fully comply with RoHS, REACH, and UL environmental directives for seamless global export.

Technical Specifications & Performance

Magnetic Grades and Energy Product Selection Guide

Selecting the correct magnetic grade depends on your operating environment and magnetic field requirements. Performance is categorized by intrinsic coercivity and maximum energy product across standard and high-temperature series:

Rade Series	Max Energy Product (BHmax)	Max Operating Temperature	Typical Application Focus
N35 - N52	33 - 52 MGOe	~ 80 deg C	High magnetic output, standard industrial motors, sensors
N35H - N48H	33 - 42 MGOe	~ 120 deg C	Servo motors, automotive sensors, elevated ambient heat
SH Series	Available upon request	~ 150 deg C	High-performance industrial automation, aerospace
UH Series	Available upon request	~ 180 deg C	Extreme thermal environments, specialized generators

Engineering Tip: Higher grades (such as N52) deliver greater magnetic output per unit volume, enabling maximum miniaturization in brushless motors and compact magnetic clamping fixtures.

Manufacturing & Quality Control Parameters

Consistency across large production lots is maintained through rigorous powder metallurgy processing:

Powder Alignment:

Vacuum melting followed by hydrogen decrepitation and magnetic field pressing to ensure uniform crystal orientation and maximum remanence.

Sintering & Machining:

Controlled thermal sintering followed by precision diamond-wheel slicing to achieve sharp edges, tight corners, and accurate rectangular profiles.

Inspection Protocols:

Every production batch undergoes strict laboratory testing for remanence (Br), coercivity (Hc), energy product (BHmax), dimensional compliance via digital micrometer gauges, and cross-cut plating adhesion checks.

Dimensional Capabilities & Customization (Build-to-Print)

Standard Profiles:

Rectangular bars, square blocks, and elongated rods available for immediate sampling.

Magnetization Directions:

Polarized through thickness, through length, through width, or complex multi-pole configurations tailored to blueprint specs.

Standard Tolerance:

+/- 0.10 mm; precision ground tolerances available to +/- 0.05 mm or tighter based on engineering drawings.

Surface Coatings and Environmental Protection

Uncoated NdFeB material oxidizes rapidly in ambient air due to its high iron content. We apply controlled electroplated or chemical layers to seal the substrate:

Ni-Cu-Ni (Nickel-Copper-Nickel):

The industry-standard multi-layer electroplating barrier protecting against dry indoor corrosion, oxidation, and regular handling wear.

Epoxy:

Applied via spray or electro-deposition to provide a robust, non-conductive, moisture-resistant barrier ideal for humid, outdoor, or marine applications.

Zinc:

A cost-effective sacrificial coating optimized for short-term indoor deployment or low-moisture environments.

Gold:

Functional over a nickel sub-layer for specialized electronic contact points, medical devices, or aesthetic requirements.

Industrial Applications & Proven Use Cases

Magnetic Separation:

Utilized extensively in chute magnets, grate magnets, and liquid trap separators to extract fine ferromagnetic particulate from food, mineral, and recycling processing lines.

Holding & Clamping Systems:

Embedded securely into welding jigs, magnetic bases, and quick-release assembly fixtures to eliminate mechanical fasteners and speed up production lines.

Electric Motors & Generators:

Integrated into permanent magnet synchronous motors, servo rotors, and wind generator sub-assemblies to optimize power-to-weight ratios and overall energy efficiency.

Sensors & Reed Switches:

Actuate magnetic proximity sensors, Hall-effect circuits, and security door contacts with highly predictable flux trigger points.

Packaging, Safety & Export Logistics

Because sintered neodymium magnets produce intense static magnetic fields, bulk wholesale shipments are packed to strictly comply with international air and ocean freight safety regulations (IATA/IMDG):

Magnetic Shielding:

Inner packaging utilizes specialized soft iron shielding sheets or engineered air gaps to completely neutralize external magnetic flux leakage during transit.

Outer Protection:

Export-grade double-walled corrugated cartons with custom high-density foam inserts to prevent chipping, corner crushing, or edge damage.

Traceability & ERP Integration:

Each master carton is clearly labeled with alloy grade, batch lot number, manufacturing date, and quantity for direct scanning and integration into client ERP systems.

FAQ

Q: What are neodymium bar magnets made of?

A: Neodymium bar magnets are manufactured from an alloy of Neodymium, Iron, and Boron (Nd2Fe14B), currently representing the strongest commercial class of rare-earth permanent magnets available.

Q: Are neodymium bar magnets stronger than ceramic (ferrite) magnets?

A: Yes. Neodymium magnets deliver several times higher magnetic energy density and holding force compared with ceramic ferrite magnets of equivalent size, allowing engineers to drastically reduce component footprints.

Q: What is the strongest commercially available grade?

A: N52 is among the strongest commercially available NdFeB grades, delivering a maximum energy product of approximately 52 MGOe.

Q: Can you manufacture custom neodymium bar magnets according to drawings?

A: Yes. We specialize in OEM build-to-print services. We customize dimensions, shapes, magnetic grades, specialized coatings, and specific magnetization orientations based on your engineering CAD files.

Q: What coating should I choose for humid or corrosive environments?

A: While Ni-Cu-Ni is standard for general indoor use, we strongly recommend an Epoxy coating or specialized multi-layer treatments for humid, damp, or marine environments to prevent long-term substrate oxidation.

Q: What maximum temperature can these magnets withstand?

A: Standard grades operate reliably up to around 80 deg C. For higher operating environments, our high-temperature series (H, SH, and UH) can withstand sustained temperatures up to 180 deg C without experiencing irreversible thermal demagnetization.

As one of the most professional neodymium bar magnets manufacturers and suppliers in China, we're featured by quality products and good service. Please rest assured to buy customized neodymium bar magnets at competitive price from our factory.