MW 14x10 / N38 - cylindrical magnet

Advantages and disadvantages of rare earth magnets.

Besides their high retention, neodymium magnets are valued for these benefits:

• They do not lose power, even over nearly ten years – the drop in power is only ~1% (according to tests),
• They have excellent resistance to weakening of magnetic properties when exposed to external fields,
• Thanks to the glossy finish, the layer of Ni-Cu-Ni, gold-plated, or silver-plated gives an aesthetic appearance,
• Magnetic induction on the top side of the magnet turns out to be extremely intense,
• Neodymium magnets are characterized by extremely high magnetic induction on the magnet surface and are able to act (depending on the form) even at a temperature of 230°C or more...
• Possibility of detailed creating and adapting to atypical conditions,
• Universal use in future technologies – they are utilized in data components, drive modules, precision medical tools, as well as technologically advanced constructions.
• Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications

Disadvantages of neodymium magnets:

• They are fragile upon too strong impacts. To avoid cracks, it is worth protecting magnets using a steel holder. Such protection not only shields the magnet but also improves its resistance to damage
• NdFeB magnets lose force when exposed to high temperatures. After reaching 80°C, many of them experience permanent weakening of strength (a factor is the shape as well as dimensions of the magnet). We offer magnets specially adapted to work at temperatures up to 230°C marked [AH], which are extremely resistant to heat
• When exposed to humidity, magnets usually rust. For applications outside, it is recommended to use protective magnets, such as magnets in rubber or plastics, which prevent oxidation as well as corrosion.
• Limited ability of creating threads in the magnet and complicated shapes - preferred is a housing - magnet mounting.
• Potential hazard related to microscopic parts of magnets pose a threat, when accidentally swallowed, which becomes key in the aspect of protecting the youngest. Furthermore, tiny parts of these devices can disrupt the diagnostic process medical after entering the body.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

Maximum lifting capacity of the magnet – what it depends on?

The specified lifting capacity refers to the maximum value, measured under laboratory conditions, meaning:

• on a base made of structural steel, effectively closing the magnetic flux
• possessing a massiveness of min. 10 mm to avoid saturation
• characterized by even structure
• without the slightest clearance between the magnet and steel
• during pulling in a direction perpendicular to the plane
• at temperature room level

Practical lifting capacity: influencing factors

Please note that the application force will differ subject to elements below, in order of importance:

• Space between surfaces – every millimeter of distance (caused e.g. by veneer or unevenness) significantly weakens the magnet efficiency, often by half at just 0.5 mm.
• Pull-off angle – note that the magnet holds strongest perpendicularly. Under sliding down, the capacity drops drastically, often to levels of 20-30% of the nominal value.
• Steel thickness – insufficiently thick plate causes magnetic saturation, causing part of the power to be escaped to the other side.
• Steel grade – ideal substrate is high-permeability steel. Stainless steels may have worse magnetic properties.
• Surface condition – smooth surfaces ensure maximum contact, which improves field saturation. Rough surfaces reduce efficiency.
• Temperature – temperature increase causes a temporary drop of force. It is worth remembering the maximum operating temperature for a given model.

* Holding force was tested on the plate surface of 20 mm thickness, when a perpendicular force was applied, whereas under attempts to slide the magnet the holding force is lower. Additionally, even a minimal clearance {between} the magnet and the plate lowers the holding force.