AM ucho [M8] - magnetic accessories

Advantages and disadvantages of NdFeB magnets.

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

• Their magnetic field is maintained, and after approximately ten years it decreases only by ~1% (according to research),
• They are noted for resistance to demagnetization induced by external field influence,
• A magnet with a smooth silver surface has an effective appearance,
• The surface of neodymium magnets generates a strong magnetic field – this is one of their assets,
• Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their form) at temperatures up to 230°C and above...
• Due to the option of flexible shaping and adaptation to unique solutions, neodymium magnets can be created in a variety of forms and dimensions, which makes them more universal,
• Key role in future technologies – they serve a role in computer drives, drive modules, advanced medical instruments, as well as industrial machines.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in tiny dimensions, which enables their usage in small systems

Disadvantages of neodymium magnets:

• They are prone to damage upon heavy impacts. To avoid cracks, it is worth securing magnets in a protective case. Such protection not only shields the magnet but also increases its resistance to damage
• We warn that neodymium magnets can lose their strength at high temperatures. To prevent this, we suggest our specialized [AH] magnets, which work effectively even at 230°C.
• Due to the susceptibility of magnets to corrosion in a humid environment, we suggest using waterproof magnets made of rubber, plastic or other material stable to moisture, in case of application outdoors
• Limited ability of producing threads in the magnet and complex shapes - recommended is casing - mounting mechanism.
• Potential hazard related to microscopic parts of magnets pose a threat, when accidentally swallowed, which is particularly important in the aspect of protecting the youngest. Furthermore, tiny parts of these devices can disrupt the diagnostic process medical when they are in the body.
• Due to expensive raw materials, their price is relatively high,

Optimal lifting capacity of a neodymium magnet – what affects it?

Information about lifting capacity was determined for optimal configuration, taking into account:

• using a sheet made of mild steel, functioning as a ideal flux conductor
• possessing a massiveness of min. 10 mm to ensure full flux closure
• with a surface free of scratches
• without any air gap between the magnet and steel
• for force applied at a right angle (pull-off, not shear)
• in stable room temperature

What influences lifting capacity in practice

In practice, the real power results from a number of factors, listed from the most important:

• Gap between surfaces – every millimeter of separation (caused e.g. by veneer or unevenness) diminishes the magnet efficiency, often by half at just 0.5 mm.
• Pull-off angle – note that the magnet holds strongest perpendicularly. Under shear forces, the capacity drops significantly, often to levels of 20-30% of the maximum value.
• Plate thickness – insufficiently thick plate does not accept the full field, causing part of the flux to be escaped into the air.
• Material type – the best choice is pure iron steel. Hardened steels may generate lower lifting capacity.
• Smoothness – ideal contact is obtained only on polished steel. Rough texture create air cushions, weakening the magnet.
• Thermal environment – temperature increase results in weakening of induction. It is worth remembering the maximum operating temperature for a given model.

* Holding force was tested on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, whereas under shearing force the load capacity is reduced by as much as fivefold. Additionally, even a small distance {between} the magnet and the plate reduces the load capacity.