e-mail: bok@dhit.pl

neodymium magnets

We provide red color magnetic Nd2Fe14B - our store's offer. All magnesy in our store are in stock for immediate purchase (check the list). See the magnet pricing for more details check the magnet price list

Magnet for treasure hunters F300 GOLD

Where to buy powerful neodymium magnet? Magnet holders in airtight, solid steel casing are excellent for use in challenging climate conditions, including snow and rain check...

magnetic holders

Holders with magnets can be applied to facilitate production processes, underwater exploration, or searching for space rocks made of ore check...

Enjoy delivery of your order on the same day before 2:00 PM on weekdays.

Dhit sp. z o.o. logo
Product available shipping tomorrow! Bestseller

MP 25x7.5/4.5x5 / N38 - neodymium magnet

ring magnet

catalog number 030194

GTIN: 5906301812111

5.0

external diameter Ø

25 mm [±0,1 mm]

internal diameter Ø

7.5/4.5 mm [±0,1 mm]

height

5 mm [±0,1 mm]

magnetizing direction

↑ axial

capacity ~

1.71 kg / 16.77 N

magnetic induction ~

333.60 mT / 3,336 Gs

max. temperature

≤ 80 °C

8.00 gross price (including VAT) / pcs +

6.50 ZŁ net price + 23% VAT / pcs

bulk discounts:

need more quantity?

price from 1 pcs
6.50 ZŁ
8.00 ZŁ
price from 93 pcs
6.11 ZŁ
7.52 ZŁ
price from 339 pcs
5.72 ZŁ
7.04 ZŁ

Want to bargain?

Call us tel: +48 22 499 98 98 or write via contact form on our website. You can check the power and the appearance of neodymium magnets in our force calculator force calculator

Orders placed by 2:00 PM will be shipped on the same business day.

Specification: ring magnet 25x7.5/4.5x5 / N38 ↑ axial

Characteristics: ring magnet 25x7.5/4.5x5 / N38 ↑ axial
Properties
Values
catalog number
030194
production / distribution
Dhit sp. z o.o.
country of origin
Poland / China / Germany
customs code
85059029
external diameter Ø
25 mm [±0,1 mm]
internal diameter Ø
7.5/4.5 mm [±0,1 mm]
height
5 mm [±0,1 mm]
magnetizing direction ?
↑ axial
capacity ~ ?
1.71 kg / 16.77 N
magnetic induction ~ ?
333.60 mT / 3,336 Gs
max. temperature ?
≤ 80 °C
coating type ?
[NiCuNi] nickel
weight
22.38 g
execution tolerance
± 0.1 mm

Magnetic properties of the material N38

material characteristics N38
Properties
Values
units
remenance Br [Min. - Max.] ?
12.2-12.6
kGs
remenance Br [Min. - Max.] ?
1220-1260
T
coercivity bHc ?
10.8-11.5
kOe
coercivity bHc ?
860-915
kA/m
actual internal force iHc
≥ 12
kOe
actual internal force iHc
≥ 955
kA/m
energy density [Min. - Max.]
36-38
BH max MGOe
energy density [Min. - Max.]
287-303
BH max KJ/m
max. temperature
≤ 80
°C

Physical properties of sintered neodymium magnets Nd2Fe14B

Physical properties of sintered neodymium magnets Nd2Fe14B
Properties
Values
units
Vickers hardness
≥550
Hv
Density
≥7.4
g/cm3
Curie Temperature TC
312 - 380
°C
Curie Temperature TF
593 - 716
°F
Specific resistance
150
μΩ⋅Cm
Bending strength
250
Mpa
Compressive strength
1000~1100
Mpa
Thermal expansion parallel (∥) to orientation (M)
(3-4) x 106
°C-1
Thermal expansion perpendicular (⊥) to orientation (M)
-(1-3) x 10-6
°C-1
Young's modulus
1.7 x 104
kg/mm²
Due to specific properties, MP 25x7.5/4.5x5 / N38 in a ring form finds extensive use in various industries. Thanks to a powerful magnetic field of 1.71 kg, which can be described as lifting capacity, they are key in applications that require strong magnetism in a compact space. Usage of MP 25x7.5/4.5x5 / N38 magnets include electric motors, generating systems, audio systems, and several other devices that use magnets for generating motion or energy storage. Despite their significant strength, they have a comparatively low weight of 22.38 grams, which makes them more convenient to use compared to heavier alternatives.
Ring magnets work due to their atomic structure. In the production process, neodymium atoms are arranged appropriately, which allows for generating a strong and precise magnetic field. This makes them perfect for devices such as stepper motors or industrial robots. Additionally, their resistance to high temperatures and demagnetization makes them indispensable in industry.
They are used in various fields of technology and industry, such as production of electronic devices, such as speakers and electric motors, the automotive industry, e.g., in the construction of electric motors, and medicine, where they are used in precision diagnostic devices. Thanks to their temperature resistance and precision makes them ideal for technologically advanced applications.
Ring magnets stand out high magnetic strength, ability to work in extreme conditions, precise control of the magnetic field. Thanks to their ring shape allows for application in devices requiring concentrated magnetic fields. Moreover, these magnets are more durable than traditional ferrite magnets, which has made them popular in advanced technologies and industrial applications.
Ring magnets perform excellently across a wide range of temperatures. They do not lose their magnetic properties, until the Curie temperature is exceeded, which for neodymium magnets is around 80°C. They are more resistant to loss of magnetism than traditional ferrite magnets. For this reason, they are ideal for applications in the automotive industry, robotics, and devices requiring operation in changing or extreme environmental conditions.

List recommended items

Advantages as well as disadvantages of neodymium magnets NdFeB.

Apart from immense power, neodymium magnets have the following advantages:

  • They do not lose power over time. After 10 years, their strength decreases by only ~1% (theoretically),
  • They are highly resistant to demagnetization by external magnetic field,
  • Thanks to the shiny finish and nickel, gold, or silver coating, they have an aesthetic appearance,
  • They possess very high magnetic induction on the surface of the magnet,
  • Magnetic neodymium magnets are characterized by very high magnetic induction on the surface of the magnet and can operate (depending on the form) even at temperatures of 230°C or higher...
  • Due to the option of accurate forming and adaptation to individual needs – neodymium magnets can be produced in a wide range of shapes and sizes, which enhances their versatility in applications.
  • Key role in advanced technologically fields – are utilized in hard drives, electric motors, medical apparatus and other highly developed apparatuses.

Disadvantages of neodymium magnets:

  • They are fragile when subjected to a powerful impact. If the magnets are exposed to impacts, we recommend using magnets in a protective case. The steel housing in the form of a holder protects the magnet from impacts, and at the same time increases its overall strength,
  • High temperatures can reduce the strength of neodymium magnets. Typically, after heating above 80°C, most of them experience a permanent reduction in strength (although it is dependent on the shape and size). To prevent this, we offer special magnets marked with the symbol [AH], which are highly resistant to high temperatures. They can operate even at temperatures up to 230°C, making them an ideal solution for applications requiring high-temperature operation,
  • Magnets exposed to a humid environment can corrode. Therefore, when using them outdoors, we suggest using waterproof magnets made of rubber, plastic, or other moisture-resistant materials,
  • The use of a cover or a magnetic holder is recommended due to the limited possibilities of manufacturing threads or complex shapes in the magnet
  • Possible danger associated with microscopic parts of magnets are risky, when accidentally ingested, which is particularly important in the aspect of protecting young children. Furthermore, small elements of these products can hinder the diagnostic process when they are in the body.

Exercise Caution with Neodymium Magnets

Neodymium magnets can become demagnetized at high temperatures.

Although magnets have shown to retain their effectiveness up to 80°C or 175°F, this temperature may vary depending on the type of material, shape, and intended use of the magnet.

Comparing neodymium magnets to ferrite magnets (found in speakers), they are 10 times more powerful, and their strength can surprise you.

Make sure to review all the information we have provided. This will help you avoid harm to your body and damage to the magnets.

Dust and powder from neodymium magnets are flammable.

Do not attempt to drill into neodymium magnets. Mechanical processing is also not recommended. If the magnet is crushed into fine powder or dust, it becomes highly flammable.

Neodymium magnetic are incredibly fragile, they easily fall apart as well as can become damaged.

Magnets made of neodymium are extremely fragile, and by joining them in an uncontrolled manner, they will break. Neodymium magnets are made of metal and coated with a shiny nickel surface, but they are not as hard as steel. In the event of a collision between two magnets, there may be a scattering of fragments in different directions. Protecting your eyes is crucial in such a situation.

Neodymium magnets are not recommended for people with pacemakers.

Neodymium magnets produce strong magnetic fields that can interfere with the operation of a heart pacemaker. However, if the magnetic field does not affect the device, it can damage its components or deactivate the device when it is in a magnetic field.

Keep neodymium magnets away from GPS and smartphones.

Magnetic fields generated by neodymium magnets interfere with compasses and magnetometers used in navigation, as well as internal compasses of smartphones and GPS devices.

Do not place neodymium magnets near a computer HDD, TV, and wallet.

Magnetic fields generated by neodymium magnets can damage magnetic storage media such as floppy disks, credit cards, magnetic ID cards, cassette tapes, video tapes, or other similar devices. In addition, they can damage televisions, VCRs, computer monitors, and CRT displays. Avoid placing neodymium magnets in close proximity to electronic devices.

The magnet coating contains nickel, so be cautious if you have a nickel allergy.

Studies show a small percentage of people have allergies to certain metals, including nickel. An allergic reaction often manifests as skin redness and rash. If you have a nickel allergy, try wearing gloves or avoid direct contact with nickel-plated neodymium magnets.

  Magnets should not be treated as toys. Therefore, it is not recommended for youngest children to have access to them.

Neodymium magnets are not toys. Be cautious and make sure no child plays with them. In the case of swallowing multiple magnets simultaneously, they can attract to each other through the intestinal walls. In the worst case scenario, this can lead to death.

Neodymium magnets can attract to each other due to their immense internal force, causing the skin and other body parts to get pinched and resulting in significant swellings.

Magnets attract each other within a distance of several to around 10 cm from each other. Remember not to put fingers between magnets or alternatively in their path when attract. Magnets, depending on their size, are able even cut off a finger or there can be a significant pressure or even a fracture.

To illustrate why neodymium magnets are so dangerous, see the article - How dangerous are very powerful neodymium magnets?.

Dhit sp. z o.o. logo

e-mail: bok@dhit.pl

tel: +48 888 99 98 98