MW 8x1.5 / N38 - cylindrical magnet

Advantages and disadvantages of NdFeB magnets.

Apart from their strong magnetic energy, neodymium magnets have these key benefits:

• They retain full power for almost ten years – the loss is just ~1% (according to analyses),
• Magnets perfectly resist against demagnetization caused by foreign field sources,
• In other words, due to the reflective surface of gold, the element is aesthetically pleasing,
• Magnets exhibit exceptionally strong magnetic induction on the outer layer,
• Due to their durability and thermal resistance, neodymium magnets can operate (depending on the shape) even at high temperatures reaching 230°C or more...
• Possibility of exact modeling and modifying to complex needs,
• Versatile presence in future technologies – they serve a role in HDD drives, electric drive systems, advanced medical instruments, and modern systems.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

What to avoid - cons of neodymium magnets and proposals for their use:

• At very strong impacts they can break, therefore we recommend placing them in steel cases. A metal housing provides additional protection against damage, as well as increases the magnet's durability.
• Neodymium magnets decrease their force under the influence of heating. As soon as 80°C is exceeded, many of them start losing their power. Therefore, we recommend our special magnets marked [AH], which maintain durability even at temperatures up to 230°C
• When exposed to humidity, magnets start to rust. To use them in conditions outside, it is recommended to use protective magnets, such as magnets in rubber or plastics, which prevent oxidation as well as corrosion.
• Due to limitations in producing nuts and complex shapes in magnets, we propose using casing - magnetic mechanism.
• Potential hazard related to microscopic parts of magnets pose a threat, if swallowed, which gains importance in the context of child safety. Furthermore, small components of these devices can disrupt the diagnostic process medical when they are in the body.
• With mass production the cost of neodymium magnets can be a barrier,

Maximum lifting force for a neodymium magnet – what affects it?

Information about lifting capacity was determined for the most favorable conditions, assuming:

• using a base made of mild steel, functioning as a magnetic yoke
• whose transverse dimension reaches at least 10 mm
• with an ideally smooth touching surface
• with total lack of distance (no paint)
• during pulling in a direction vertical to the mounting surface
• at ambient temperature room level

Magnet lifting force in use – key factors

During everyday use, the real power results from a number of factors, presented from most significant:

• Gap (betwixt the magnet and the metal), since even a very small clearance (e.g. 0.5 mm) can cause a drastic drop in lifting capacity by up to 50% (this also applies to paint, corrosion or debris).
• Force direction – remember that the magnet holds strongest perpendicularly. Under sliding down, the capacity drops drastically, often to levels of 20-30% of the nominal value.
• Base massiveness – insufficiently thick plate does not accept the full field, causing part of the power to be escaped to the other side.
• Steel grade – ideal substrate is high-permeability steel. Hardened steels may generate lower lifting capacity.
• Smoothness – ideal contact is possible only on smooth steel. Any scratches and bumps create air cushions, weakening the magnet.
• Thermal conditions – neodymium magnets have a sensitivity to temperature. At higher temperatures they lose power, and at low temperatures gain strength (up to a certain limit).

* Holding force was tested on the plate surface of 20 mm thickness, when the force acted perpendicularly, whereas under attempts to slide the magnet the load capacity is reduced by as much as 5 times. In addition, even a slight gap {between} the magnet’s surface and the plate decreases the lifting capacity.