UMGW 60x30x15 [M10] GW / N38 - magnetic holder internal thread

Advantages and disadvantages of neodymium magnets NdFeB.

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

• They do not lose their even during nearly ten years – the reduction of strength is only ~1% (theoretically),
• They remain magnetized despite exposure to strong external fields,
• By applying a shiny layer of gold, the element gains a modern look,
• The outer field strength of the magnet shows elevated magnetic properties,
• They are suitable for high-temperature applications, operating effectively at 230°C+ due to advanced heat resistance and form-specific properties,
• With the option for tailored forming and targeted design, these magnets can be produced in multiple shapes and sizes, greatly improving engineering flexibility,
• Wide application in advanced technical fields – they are used in computer drives, electric motors, diagnostic apparatus along with other advanced devices,
• Compactness – despite their small size, they provide high effectiveness, making them ideal for precision applications

Disadvantages of NdFeB magnets:

• They are fragile when subjected to a powerful impact. If the magnets are exposed to shocks, it is suggested to place them in a steel housing. The steel housing, in the form of a holder, protects the magnet from damage and additionally strengthens its overall durability,
• They lose strength at high temperatures. Most neodymium magnets experience permanent loss in strength when heated above 80°C (depending on the dimensions and height). However, we offer special variants with high temperature resistance that can operate up to 230°C or higher,
• They rust in a wet environment – during outdoor use, we recommend using waterproof magnets, such as those made of non-metallic materials,
• The use of a protective casing or external holder is recommended, since machining fine details in neodymium magnets is difficult,
• Health risk due to small fragments may arise, especially if swallowed, which is significant in the context of child safety. Furthermore, miniature parts from these magnets may complicate medical imaging once in the system,
• Due to a complex production process, their cost is relatively high,

Maximum lifting force for a neodymium magnet – what contributes to it?

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

• using a steel plate with low carbon content, acting as a magnetic circuit closure
• having a thickness of no less than 10 millimeters
• with a refined outer layer
• with zero air gap
• in a perpendicular direction of force
• under standard ambient temperature

Key elements affecting lifting force

In practice, the holding capacity of a magnet is affected by these factors, arranged from the most important to the least relevant:

• Air gap between the magnet and the plate, since even a very small distance (e.g. 0.5 mm) causes 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 measured on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, however under shearing force the holding force is lower. In addition, even a slight gap {between} the magnet and the plate reduces the load capacity.