UMGB 135x40 [M10+M12] GW F600 +Lina GOBLIN / N38 - goblin magnetic holder

Advantages as well as disadvantages of neodymium magnets NdFeB.

In addition to their magnetic capacity, neodymium magnets provide the following advantages:

• They retain their full power for around ten years – the loss is just ~1% (according to analyses),
• They are very resistant to demagnetization caused by external magnetic sources,
• In other words, due to the shiny silver coating, the magnet obtains an stylish appearance,
• They exhibit superior levels of magnetic induction near the outer area of the magnet,
• With the right combination of compounds, they reach excellent thermal stability, enabling operation at or above 230°C (depending on the structure),
• The ability for custom shaping or adjustment to individual needs – neodymium magnets can be manufactured in multiple variants of geometries, which extends the scope of their use cases,
• Significant impact in cutting-edge sectors – they find application in hard drives, electric motors, medical equipment along with high-tech tools,
• Compactness – despite their small size, they generate strong force, making them ideal for precision applications

Disadvantages of neodymium magnets:

• They are prone to breaking when subjected to a strong impact. If the magnets are exposed to shocks, they should be placed in a protective enclosure. The steel housing, in the form of a holder, protects the magnet from breakage and strengthens its overall strength,
• High temperatures may significantly reduce the holding force of neodymium magnets. Typically, above 80°C, they experience permanent loss in performance (depending on size). 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 moist environment – during outdoor use, we recommend using sealed magnets, such as those made of polymer,
• Limited ability to create threads in the magnet – the use of a mechanical support is recommended,
• Potential hazard due to small fragments may arise, if ingested accidentally, which is crucial in the family environments. Additionally, minuscule fragments from these products might hinder health screening after being swallowed,
• In cases of large-volume purchasing, neodymium magnet cost may not be economically viable,

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

The given lifting capacity of the magnet corresponds to the maximum lifting force, calculated in ideal conditions, specifically:

• with mild steel, serving as a magnetic flux conductor
• of a thickness of at least 10 mm
• with a smooth surface
• with zero air gap
• under perpendicular detachment force
• in normal thermal conditions

Lifting capacity in real conditions – 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, as 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.

* Lifting capacity was assessed with the use of a polished steel plate of suitable thickness (min. 20 mm), under vertically applied force, however under attempts to slide the magnet the lifting capacity is smaller. In addition, even a minimal clearance {between} the magnet and the plate reduces the load capacity.