UMGGZ 43x6 [M6] GZ / N38 - rubber magnetic holder external thread

Advantages and disadvantages of neodymium magnets NdFeB.

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

• They retain their full power for around 10 years – the drop is just ~1% (in theory),
• They protect against demagnetization induced by surrounding magnetic influence effectively,
• In other words, due to the glossy silver coating, the magnet obtains an professional appearance,
• The outer field strength of the magnet shows advanced magnetic properties,
• They are suitable for high-temperature applications, operating effectively at 230°C+ due to advanced heat resistance and form-specific properties,
• The ability for accurate shaping as well as adaptation to specific needs – neodymium magnets can be manufactured in multiple variants of geometries, which enhances their versatility in applications,
• Important function in cutting-edge sectors – they are utilized in hard drives, rotating machines, diagnostic apparatus as well as technologically developed systems,
• Compactness – despite their small size, they deliver powerful magnetism, making them ideal for precision applications

Disadvantages of neodymium magnets:

• They can break when subjected to a strong impact. If the magnets are exposed to physical collisions, it is suggested to place them in a metal holder. The steel housing, in the form of a holder, protects the magnet from cracks and increases its overall strength,
• High temperatures may significantly reduce the magnetic power of neodymium magnets. Typically, above 80°C, they experience permanent loss in performance (depending on height). To prevent this, we offer heat-resistant magnets marked [AH], capable of working up to 230°C, which makes them perfect for high-temperature use,
• They rust in a humid environment. If exposed to rain, we recommend using encapsulated magnets, such as those made of plastic,
• Using a cover – such as a magnetic holder – is advised due to the restrictions in manufacturing threads directly in the magnet,
• Possible threat linked to microscopic shards may arise, if ingested accidentally, which is notable in the context of child safety. Furthermore, miniature parts from these magnets may interfere with diagnostics after being swallowed,
• High unit cost – neodymium magnets are pricier than other types of magnets (e.g., ferrite), which may limit large-scale applications

Best holding force of the magnet in ideal parameters – what it depends on?

The given lifting capacity of the magnet means the maximum lifting force, assessed in ideal conditions, namely:

• with mild steel, used as a magnetic flux conductor
• having a thickness of no less than 10 millimeters
• with a polished side
• with zero air gap
• under perpendicular detachment force
• under standard ambient temperature

Impact of factors on magnetic holding capacity in practice

In practice, the holding capacity of a magnet is affected by these factors, from crucial to less important:

• Air gap between the magnet and the plate, because even a very small distance (e.g. 0.5 mm) can cause a drop in lifting force of up to 50%.
• Direction of applied force, because the maximum lifting capacity is achieved under perpendicular application. The force required to slide the magnet along the plate is usually several times lower.
• Thickness of the plate, as a plate that is too thin causes part of the magnetic flux not to be used and to remain wasted in the air.
• Material of the plate, because higher carbon content lowers holding force, while higher iron content increases it. The best choice is steel with high magnetic permeability and high saturation induction.
• Surface of the plate, because the more smooth and polished it is, the better the contact and consequently the greater the magnetic saturation.
• Operating temperature, since all permanent magnets have a negative temperature coefficient. This means that at high temperatures they are weaker, while at sub-zero temperatures they become slightly stronger.

* Lifting capacity testing was conducted on plates with a smooth surface of suitable thickness, under perpendicular forces, in contrast under shearing force the holding force is lower. Moreover, even a slight gap {between} the magnet and the plate reduces the lifting capacity.