MP 40x10.4/5.5x5 / N38 - ring magnet
ring magnet
Catalog no 030249
GTIN: 5906301812258
Diameter [±0,1 mm]
40 mm
internal diameter Ø [±0,1 mm]
10.4/5.5 mm
Height [±0,1 mm]
5 mm
Weight
37.76 g
Magnetization Direction
↑ axial
Load capacity
2.27 kg / 22.26 N
Magnetic Induction
391.66 mT
Coating
[NiCuNi] nickel
27.00 ZŁ with VAT / pcs + price for transport
21.95 ZŁ net + 23% VAT / pcs
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MP 40x10.4/5.5x5 / N38 - ring magnet
Magnetic properties of material N38
Physical properties of NdFeB
Shopping tips
Advantages as well as disadvantages of neodymium magnets NdFeB.
Apart from their superior power, neodymium magnets have these key benefits:
- They have stable power, and over around 10 years their performance decreases symbolically – ~1% (according to theory),
- Their ability to resist magnetic interference from external fields is notable,
- Thanks to the shiny finish and gold coating, they have an aesthetic appearance,
- They exhibit elevated levels of magnetic induction near the outer area of the magnet,
- They are suitable for high-temperature applications, operating effectively at 230°C+ due to advanced heat resistance and form-specific properties,
- Thanks to the possibility in shaping and the capability to adapt to specific requirements, neodymium magnets can be created in diverse shapes and sizes, which expands their functional possibilities,
- Wide application in advanced technical fields – they are utilized in data storage devices, electric drives, medical equipment and technologically developed systems,
- Thanks to their efficiency per volume, small magnets offer high magnetic performance, while occupying minimal space,
Disadvantages of NdFeB magnets:
- They are prone to breaking when subjected to a strong impact. If the magnets are exposed to physical collisions, it is advisable to use in a steel housing. The steel housing, in the form of a holder, protects the magnet from cracks and increases its overall durability,
- They lose power at elevated temperatures. Most neodymium magnets experience permanent decline in strength when heated above 80°C (depending on the dimensions and height). However, we offer special variants with high temperature resistance that can operate up to 230°C or higher,
- They rust in a humid environment – during outdoor use, we recommend using encapsulated magnets, such as those made of non-metallic materials,
- Limited ability to create complex details in the magnet – the use of a external casing is recommended,
- Potential hazard related to magnet particles may arise, if ingested accidentally, which is crucial in the protection of children. Additionally, small elements from these assemblies may hinder health screening if inside the body,
- Higher purchase price is one of the drawbacks compared to ceramic magnets, especially in budget-sensitive applications
Maximum lifting capacity of the magnet – what it depends on?
The given holding capacity of the magnet means the highest holding force, assessed under optimal conditions, that is:
- with mild steel, serving as a magnetic flux conductor
- with a thickness of minimum 10 mm
- with a polished side
- in conditions of no clearance
- under perpendicular detachment force
- in normal thermal conditions
Determinants of lifting force in real conditions
In practice, the holding capacity of a magnet is conditioned by the following aspects, arranged from the most important to the least relevant:
- Air gap between the magnet and the plate, as even a very small distance (e.g. 0.5 mm) causes a drop in lifting force of up to 50%.
- Direction of applied force, because the maximum lifting capacity is achieved under perpendicular application. The force required to slide the magnet along the plate is usually several times lower.
- Thickness of the plate, as a plate that is too thin causes part of the magnetic flux not to be used and to remain wasted in the air.
- Material of the plate, because higher carbon content lowers holding force, while higher iron content increases it. The best choice is steel with high magnetic permeability and high saturation induction.
- Surface of the plate, because the more smooth and polished it is, the better the contact and consequently the greater the magnetic saturation.
- Operating temperature, since all permanent magnets have a negative temperature coefficient. This means that at high temperatures they are weaker, while at sub-zero temperatures they become slightly stronger.
* Holding force was tested on a smooth steel plate of 20 mm thickness, when a perpendicular force was applied, in contrast under shearing force the lifting capacity is smaller. Additionally, even a slight gap {between} the magnet and the plate decreases the load capacity.
Safety Guidelines with Neodymium Magnets
Neodymium magnetic are highly susceptible to damage, resulting in shattering.
Neodymium magnets are characterized by significant fragility. Magnets made of neodymium are made of metal and coated with a shiny nickel, but they are not as durable 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.
The magnet coating is made of nickel, so be cautious if you have an allergy.
Studies clearly indicate a small percentage of people who suffer from metal allergies such as nickel. An allergic reaction often manifests as skin redness and rash. If you have a nickel allergy, you can try wearing gloves or simply avoid direct contact with nickel-plated neodymium magnets.
You should maintain neodymium magnets at a safe distance from the wallet, computer, and TV.
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. You should especially avoid placing neodymium magnets near electronic devices.
Neodymium magnets can demagnetize 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.
Dust and powder from neodymium magnets are flammable.
Avoid drilling or mechanical processing of neodymium magnets. Once crushed into fine powder or dust, this material becomes highly flammable.
Never bring neodymium magnets close to a phone and GPS.
Neodymium magnets produce intense magnetic fields that interfere with magnetometers and compasses used in navigation, as well as internal compasses of smartphones and GPS devices.
Neodymium magnets should not be in the vicinity youngest children.
Remember that 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 are the most powerful magnets ever created, and their strength can shock you.
To handle magnets properly, it is best to familiarize yourself with our information beforehand. This will help you avoid significant harm to your body and the magnets themselves.
Neodymium magnets are not recommended for people with pacemakers.
Neodymium magnets generate very strong magnetic fields that can interfere with the operation of a pacemaker. This happens because such devices have a function to deactivate them in a magnetic field.
It is crucial not to allow the magnets to pinch together uncontrollably or place your fingers in their path as they attract to each other.
Magnets will attract each other within a distance of several to around 10 cm from each other. Don't put your fingers in the path of magnet attraction, because a significant injury may occur. Magnets, depending on their size, can even cut off a finger or alternatively there can be a severe pressure or even a fracture.
Safety precautions!
To illustrate why neodymium magnets are so dangerous, read the article - How dangerous are powerful neodymium magnets?.