Permanent Arc Neodymium Magnet


Motor Segment Neodymium Magnet Feature:

Part No.: 35HNBS1.1/813/4-45

Dimensions: 1 1/8” o.r. x 1” i.r. x 3/4” x 45

Material: Neodymium, Grade N35H

Plating/Coating:  Color-Zinc

Magnetization Direction: North on outside face

Max. Operating Temperature: 120°C

Applications of Neodymium Magnets

Magnetic separators

Linear actuators

Microphone assemblies

Servo motors

DC motors (automotive starters)

Computer rigid disc drives, printers and speakers


For as-pressed material, tolerance on the thickness (direction of magnetization) is +/– .005”. Other dimensions are +/– 2.5% or +/– .005”, whichever is greater.

According to International Magnetics Association/Magnet Materials Producers Association (IMA/MMPA) standards, visual imperfections such as hairline cracks, porosity and minor chips are commonly found in sintered magnets. A chipped edge is considered acceptable if no more than 10% of the surface is missing. Cracks are acceptable as long as they do not extend across more than 50% of the pole’s surface.

Attributes of Neodymium Material

Very high resistance to demagnetization

High energy for size

Good in ambient temperature

Moderately priced

Material is corrosive and should be coated for long term maximum energy output

Low working temperature for heat applications, but higher levels of heat resistance materials are being introduced periodically


Since neodymium magnet material is prone to chipping and cracking, it does not lend itself to conventional machining methods. However, neodymium can be abrasively ground, but only with the use of liberal amounts of coolant. The coolant minimizes heat fracturing and the risk of fires caused by oxidized grinding dust.

Magnetizing and Handling

Neodymium magnets are very brittle and very strong magnetically. Therefore, it is crucial to handle these magnets with extreme care to avoid personal injury and damage to the magnets. Fingers can be severely pinched between attracting magnets. Magnets can chip if allowed to “jump at” an attracting object. It is highly recommended that when constructing rare earth magnetic assemblies, they be magnetized after assembly.

Motor Magnets / Rare earth magnets are mostly used in motor, such as permanent magnet D.C. motors, wound field D.C. motors, gear motors, custom D.C. motors. generator or electric motor; electrical machinery. 

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