NC NeoCube fi 5 mm kuleczki srebrne / N38 - neocube

Advantages as well as disadvantages of neodymium magnets NdFeB.

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

• They virtually do not lose power, because even after 10 years, the performance loss is only ~1% (according to literature),
• They protect against demagnetization induced by surrounding magnetic fields effectively,
• Thanks to the polished finish and gold coating, they have an aesthetic appearance,
• They have very high magnetic induction on the surface of the magnet,
• Thanks to their high temperature resistance, they can operate (depending on the shape) even at temperatures up to 230°C or more,
• The ability for accurate shaping and customization to specific needs – neodymium magnets can be manufactured in multiple variants of geometries, which enhances their versatility in applications,
• Wide application in modern technologies – they are utilized in computer drives, rotating machines, clinical machines or even other advanced devices,
• Compactness – despite their small size, they deliver powerful magnetism, making them ideal for precision applications

Disadvantages of magnetic elements:

• They are fragile when subjected to a powerful impact. If the magnets are exposed to external force, it is advisable to use in a metal holder. The steel housing, in the form of a holder, protects the magnet from breakage while also enhances its overall strength,
• High temperatures may significantly reduce the holding force of neodymium magnets. Typically, above 80°C, they experience permanent decline in performance (depending on shape). 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 wet environment, especially when used outside, we recommend using encapsulated magnets, such as those made of non-metallic materials,
• Using a cover – such as a magnetic holder – is advised due to the challenges in manufacturing fine shapes directly in the magnet,
• Potential hazard linked to microscopic shards may arise, in case of ingestion, which is notable in the health of young users. Moreover, tiny components from these devices have the potential to interfere with diagnostics once in the system,
• High unit cost – neodymium magnets are more expensive than other types of magnets (e.g., ferrite), which increases the cost of large-scale applications

Maximum magnetic pulling force – what contributes to it?

The given lifting capacity of the magnet corresponds to the maximum lifting force, determined in the best circumstances, that is:

• using a steel plate with low carbon content, serving as a magnetic circuit closure
• with a thickness of minimum 10 mm
• with a refined outer layer
• with zero air gap
• with vertical force applied
• at room temperature

Practical lifting capacity: influencing factors

In practice, the holding capacity of a magnet is conditioned by the following aspects, arranged from the most important to the least relevant:

• Air gap between the magnet and the plate, as 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 was measured by applying a steel plate with a smooth surface of optimal thickness (min. 20 mm), under vertically applied force, in contrast under shearing force the holding force is lower. Additionally, even a minimal clearance {between} the magnet’s surface and the plate reduces the lifting capacity.