MW 6x2 / N38 - cylindrical magnet

Pros and cons of rare earth magnets.

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

• They have unchanged lifting capacity, and over around 10 years their performance decreases symbolically – ~1% (according to theory),
• Neodymium magnets are remarkably resistant to magnetic field loss caused by external interference,
• By covering with a shiny layer of gold, the element presents an nice look,
• Magnetic induction on the working part of the magnet is strong,
• Due to their high temperature resistance, they can operate (depending on the shape) even at temperatures up to 230°C or more,
• Possibility of accurate creating and optimizing to individual needs,
• Fundamental importance in modern technologies – they are used in mass storage devices, electric motors, medical equipment, also complex engineering applications.
• Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in small dimensions, which allows their use in miniature devices

Disadvantages of neodymium magnets:

• To avoid cracks upon strong impacts, we recommend using special steel holders. Such a solution protects the magnet and simultaneously increases its durability.
• Neodymium magnets demagnetize when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop 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 very resistant to heat
• When exposed to humidity, magnets usually rust. To use them in conditions outside, it is recommended to use protective magnets, such as magnets in rubber or plastics, which secure oxidation and corrosion.
• Due to limitations in producing threads and complicated forms in magnets, we propose using a housing - magnetic mechanism.
• Possible danger to health – tiny shards of magnets pose a threat, if swallowed, which gains importance in the context of child safety. Additionally, tiny parts of these devices are able to disrupt the diagnostic process medical in case of swallowing.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

Maximum lifting force for a neodymium magnet – what it depends on?

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

• on a plate made of mild steel, perfectly concentrating the magnetic field
• whose thickness is min. 10 mm
• characterized by even structure
• without the slightest air gap between the magnet and steel
• during detachment in a direction vertical to the plane
• in temp. approx. 20°C

Magnet lifting force in use – key factors

In real-world applications, the actual holding force depends on several key aspects, presented from the most important:

• Space between magnet and steel – even a fraction of a millimeter of separation (caused e.g. by veneer or unevenness) drastically reduces the magnet efficiency, often by half at just 0.5 mm.
• Direction of force – highest force is obtained only during pulling at a 90° angle. The resistance to sliding of the magnet along the plate is usually many times lower (approx. 1/5 of the lifting capacity).
• Base massiveness – too thin plate causes magnetic saturation, causing part of the power to be escaped into the air.
• Steel type – low-carbon steel attracts best. Alloy steels reduce magnetic permeability and lifting capacity.
• Surface structure – the smoother and more polished the plate, the better the adhesion and stronger the hold. Roughness creates an air distance.
• Temperature – heating the magnet results in weakening of induction. It is worth remembering the maximum operating temperature for a given model.

* Lifting capacity was measured by applying a steel plate with a smooth surface of optimal thickness (min. 20 mm), under vertically applied force, whereas under parallel forces the holding force is lower. Moreover, even a minimal clearance {between} the magnet and the plate reduces the load capacity.