MW 12x4 / N52 - cylindrical magnet

Pros as well as cons of NdFeB magnets.

Apart from their superior magnetism, neodymium magnets have these key benefits:

• They have constant strength, and over more than ten years their performance decreases symbolically – ~1% (according to theory),
• Neodymium magnets are distinguished by remarkably resistant to loss of magnetic properties caused by magnetic disturbances,
• Thanks to the glossy finish, the coating of Ni-Cu-Ni, gold, or silver-plated gives an modern appearance,
• Magnets are characterized by extremely high magnetic induction on the active area,
• Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their form) at temperatures up to 230°C and above...
• Possibility of detailed modeling and optimizing to atypical applications,
• Wide application in electronics industry – they are commonly used in HDD drives, electric motors, medical equipment, as well as modern systems.
• Relatively small size with high pulling force – neodymium magnets offer high power in tiny dimensions, which makes them useful in miniature devices

Disadvantages of neodymium magnets:

• To avoid cracks under impact, we suggest using special steel holders. Such a solution secures the magnet and simultaneously increases its durability.
• Neodymium magnets demagnetize when exposed to high temperatures. After reaching 80°C, many of them experience permanent weakening of power (a factor is the shape and 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.
• We recommend cover - magnetic holder, due to difficulties in creating threads inside the magnet and complicated forms.
• Health risk resulting from small fragments of magnets are risky, in case of ingestion, which is particularly important in the context of child health protection. Additionally, small elements of these devices can disrupt the diagnostic process medical after entering the body.
• Due to neodymium price, their price is relatively high,

Best holding force of the magnet in ideal parameters – what contributes to it?

Information about lifting capacity is the result of a measurement for the most favorable conditions, taking into account:

• on a plate made of structural steel, perfectly concentrating the magnetic field
• with a thickness no less than 10 mm
• with an ground contact surface
• with direct contact (no coatings)
• under axial force direction (90-degree angle)
• at temperature room level

Magnet lifting force in use – key factors

It is worth knowing that the application force will differ depending on elements below, starting with the most relevant:

• Space between surfaces – even a fraction of a millimeter of separation (caused e.g. by varnish or dirt) significantly weakens the pulling force, often by half at just 0.5 mm.
• Force direction – catalog parameter refers to pulling vertically. When slipping, the magnet holds much less (typically approx. 20-30% of maximum force).
• Plate thickness – insufficiently thick plate does not close the flux, causing part of the flux to be lost to the other side.
• Chemical composition of the base – mild steel attracts best. Alloy admixtures lower magnetic properties and lifting capacity.
• Surface finish – full contact is possible only on smooth steel. Any scratches and bumps create air cushions, weakening the magnet.
• Temperature – heating the magnet causes a temporary drop of force. It is worth remembering the maximum operating temperature for a given model.

* Holding force was measured on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, in contrast under shearing force the holding force is lower. Additionally, even a small distance {between} the magnet’s surface and the plate lowers the load capacity.