UMGZ 32x18x8 [M6] GZ / N38 - magnetic holder external thread

Advantages and disadvantages of neodymium magnets NdFeB.

Besides their magnetic performance, neodymium magnets are valued for these benefits:

• They do not lose their power around 10 years – the reduction of power is only ~1% (based on measurements),
• They remain magnetized despite exposure to magnetic noise,
• By applying a bright layer of silver, the element gains a modern look,
• They exhibit superior levels of magnetic induction near the outer area of the magnet,
• With the right combination of magnetic alloys, they reach increased thermal stability, enabling operation at or above 230°C (depending on the design),
• Thanks to the flexibility in shaping and the capability to adapt to individual requirements, neodymium magnets can be created in various configurations, which increases their usage potential,
• Key role in modern technologies – they serve a purpose in computer drives, electromechanical systems, diagnostic apparatus as well as sophisticated instruments,
• Thanks to their power density, small magnets offer high magnetic performance, with minimal size,

Disadvantages of neodymium magnets:

• They are prone to breaking when subjected to a strong impact. If the magnets are exposed to external force, it is advisable to use in a protective case. The steel housing, in the form of a holder, protects the magnet from damage , and at the same time enhances its overall strength,
• They lose strength at increased temperatures. Most neodymium magnets experience permanent loss in strength when heated above 80°C (depending on the shape and height). However, we offer special variants with high temperature resistance that can operate up to 230°C or higher,
• They rust in a damp environment, especially when used outside, we recommend using sealed magnets, such as those made of rubber,
• Using a cover – such as a magnetic holder – is advised due to the challenges in manufacturing fine shapes directly in the magnet,
• Possible threat linked to microscopic shards may arise, especially if swallowed, which is notable in the family environments. It should also be noted that tiny components from these devices have the potential to interfere with diagnostics if inside the body,
• In cases of mass production, neodymium magnet cost may not be economically viable,

Maximum holding power of the magnet – what contributes to it?

The given lifting capacity of the magnet represents the maximum lifting force, determined in ideal conditions, namely:

• with the use of low-carbon steel plate acting as a magnetic yoke
• having a thickness of no less than 10 millimeters
• with a refined outer layer
• with no separation
• with vertical force applied
• at room temperature

Magnet lifting force in use – key factors

Practical lifting force is determined by factors, listed from the most critical to the less significant:

• Air gap between the magnet and the plate, since 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.

* Holding force was tested on the plate surface of 20 mm thickness, when a perpendicular force was applied, however under attempts to slide the magnet the lifting capacity is smaller. In addition, even a small distance {between} the magnet’s surface and the plate lowers the load capacity.