MP 5x2.7/1.2x5 C / N38 - ring magnet

Pros as well as cons of NdFeB magnets.

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

• They have stable power, and over around ten years their performance decreases symbolically – ~1% (in testing),
• They retain their magnetic properties even under strong external field,
• In other words, due to the aesthetic layer of gold, the element is aesthetically pleasing,
• Neodymium magnets generate maximum magnetic induction on a small surface, which allows for strong attraction,
• Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their shape) at temperatures up to 230°C and above...
• Thanks to versatility in forming and the capacity to customize to complex applications,
• Significant place in electronics industry – they are used in computer drives, electric drive systems, diagnostic systems, and industrial machines.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

Disadvantages of NdFeB magnets:

• To avoid cracks under impact, we suggest using special steel holders. Such a solution protects the magnet and simultaneously improves its durability.
• Neodymium magnets demagnetize when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop of power (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 producing threads in the magnet and complex shapes - recommended is a housing - mounting mechanism.
• Health risk related to microscopic parts of magnets can be dangerous, in case of ingestion, which becomes key in the aspect of protecting the youngest. It is also worth noting that tiny parts of these products are able to be problematic in diagnostics medical after entering the body.
• With mass production the cost of neodymium magnets is a challenge,

Detachment force of the magnet in optimal conditions – what affects it?

Breakaway force is the result of a measurement for optimal configuration, assuming:

• using a base made of high-permeability steel, functioning as a ideal flux conductor
• whose thickness reaches at least 10 mm
• with a plane perfectly flat
• without the slightest insulating layer between the magnet and steel
• under vertical force direction (90-degree angle)
• at ambient temperature room level

Lifting capacity in real conditions – factors

It is worth knowing that the magnet holding will differ subject to elements below, starting with the most relevant:

• Distance – the presence of foreign body (paint, dirt, gap) interrupts the magnetic circuit, which lowers power rapidly (even by 50% at 0.5 mm).
• Angle of force application – highest force is reached only during pulling at a 90° angle. The resistance to sliding of the magnet along the plate is standardly several times smaller (approx. 1/5 of the lifting capacity).
• Element thickness – for full efficiency, the steel must be adequately massive. Thin sheet limits the attraction force (the magnet "punches through" it).
• Chemical composition of the base – mild steel attracts best. Alloy admixtures decrease magnetic properties and lifting capacity.
• Surface quality – the smoother and more polished the plate, the larger the contact zone and higher the lifting capacity. Unevenness acts like micro-gaps.
• Thermal factor – high temperature reduces magnetic field. Exceeding the limit temperature can permanently damage the magnet.

* Holding force was checked on the plate surface of 20 mm thickness, when the force acted perpendicularly, in contrast under parallel forces the load capacity is reduced by as much as 5 times. Moreover, even a minimal clearance {between} the magnet’s surface and the plate lowers the lifting capacity.