UMP 107x40 [M8+M10] GW F 400 kg / N38 - search holder

Pros and cons of NdFeB magnets.

Besides their remarkable strength, neodymium magnets offer the following advantages:

• They have stable power, and over around ten years their performance decreases symbolically – ~1% (in testing),
• They have excellent resistance to magnetic field loss as a result of external fields,
• The use of an aesthetic coating of noble metals (nickel, gold, silver) causes the element to present itself better,
• Magnetic induction on the working part of the magnet remains exceptional,
• Through (adequate) combination of ingredients, they can achieve high thermal strength, allowing for operation at temperatures approaching 230°C and above...
• Thanks to versatility in constructing and the capacity to adapt to unusual requirements,
• Wide application in modern technologies – they serve a role in HDD drives, drive modules, medical equipment, also modern systems.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

What to avoid - cons of neodymium magnets: tips and applications.

• At very strong impacts they can crack, therefore we advise placing them in steel cases. A metal housing provides additional protection against damage and increases the magnet's durability.
• When exposed to high temperature, neodymium magnets experience a drop in power. Often, when the temperature exceeds 80°C, their power decreases (depending on the size, as well as shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
• Due to the susceptibility of magnets to corrosion in a humid environment, we suggest using waterproof magnets made of rubber, plastic or other material immune to moisture, when using outdoors
• Due to limitations in realizing threads and complicated forms in magnets, we propose using cover - magnetic mount.
• Possible danger related to microscopic parts of magnets are risky, if swallowed, which becomes key in the aspect of protecting the youngest. Furthermore, small elements of these devices are able to complicate diagnosis medical in case of swallowing.
• With budget limitations the cost of neodymium magnets can be a barrier,

Magnetic strength at its maximum – what affects it?

Holding force of 480 kg is a theoretical maximum value conducted under specific, ideal conditions:

• on a block made of mild steel, optimally conducting the magnetic flux
• whose thickness equals approx. 10 mm
• characterized by smoothness
• with zero gap (without impurities)
• during pulling in a direction vertical to the plane
• at conditions approx. 20°C

Lifting capacity in practice – influencing factors

In practice, the actual holding force results from several key aspects, listed from the most important:

• Gap between surfaces – even a fraction of a millimeter of distance (caused e.g. by varnish or unevenness) significantly weakens the pulling force, often by half at just 0.5 mm.
• Load vector – highest force is available only during pulling at a 90° angle. The resistance to sliding of the magnet along the plate is standardly several times lower (approx. 1/5 of the lifting capacity).
• Element thickness – to utilize 100% power, the steel must be sufficiently thick. Paper-thin metal restricts the attraction force (the magnet "punches through" it).
• Metal type – not every steel attracts identically. Alloy additives worsen the attraction effect.
• Plate texture – smooth surfaces ensure maximum contact, which increases field saturation. Rough surfaces reduce efficiency.
• Thermal conditions – NdFeB sinters have a negative temperature coefficient. When it is hot they lose power, and in frost gain strength (up to a certain limit).

* Holding force was tested on the plate surface of 20 mm thickness, when a perpendicular force was applied, whereas under parallel forces the lifting capacity is smaller. In addition, even a minimal clearance {between} the magnet’s surface and the plate decreases the load capacity.