AM ucho [M12] - magnetic accessories

Strengths as well as weaknesses of rare earth magnets.

Apart from their notable magnetism, neodymium magnets have these key benefits:

• They virtually do not lose strength, because even after ten years the performance loss is only ~1% (in laboratory conditions),
• They have excellent resistance to magnetism drop as a result of external fields,
• By using a decorative coating of gold, the element has an elegant look,
• Magnets possess huge magnetic induction on the active area,
• Through (appropriate) combination of ingredients, they can achieve high thermal strength, allowing for operation at temperatures approaching 230°C and above...
• Thanks to the possibility of free shaping and customization to individualized requirements, NdFeB magnets can be manufactured in a wide range of forms and dimensions, which increases their versatility,
• Key role in modern technologies – they are commonly used in HDD drives, electric motors, advanced medical instruments, as well as complex engineering applications.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in small dimensions, which makes them useful in compact constructions

Disadvantages of neodymium magnets:

• To avoid cracks upon strong impacts, we recommend using special steel holders. Such a solution protects the magnet and simultaneously improves its durability.
• Neodymium magnets decrease their power under the influence of heating. As soon as 80°C is exceeded, many of them start losing their power. Therefore, we recommend our special magnets marked [AH], which maintain durability even at temperatures up to 230°C
• Magnets exposed to a humid environment can rust. Therefore during using outdoors, we recommend using waterproof magnets made of rubber, plastic or other material resistant to moisture
• Due to limitations in creating threads and complicated shapes in magnets, we recommend using cover - magnetic holder.
• Potential hazard to health – tiny shards of magnets are risky, in case of ingestion, which is particularly important in the aspect of protecting the youngest. Furthermore, small elements of these devices are able to complicate diagnosis medical after entering the body.
• Due to complex production process, their price is relatively high,

Highest magnetic holding force – what it depends on?

Magnet power was determined for the most favorable conditions, assuming:

• on a base made of mild steel, perfectly concentrating the magnetic flux
• whose transverse dimension equals approx. 10 mm
• with a surface perfectly flat
• without any air gap between the magnet and steel
• under axial force vector (90-degree angle)
• in stable room temperature

Impact of factors on magnetic holding capacity in practice

It is worth knowing that the magnet holding will differ subject to the following factors, in order of importance:

• Clearance – the presence of foreign body (rust, tape, gap) acts as an insulator, which lowers power rapidly (even by 50% at 0.5 mm).
• Force direction – declared lifting capacity refers to detachment vertically. When attempting to slide, the magnet exhibits much less (often approx. 20-30% of nominal force).
• Metal thickness – thin material does not allow full use of the magnet. Part of the magnetic field passes through the material instead of generating force.
• Material type – the best choice is pure iron steel. Hardened steels may generate lower lifting capacity.
• Base smoothness – the more even the surface, the better the adhesion and higher the lifting capacity. Roughness creates an air distance.
• Thermal factor – hot environment reduces magnetic field. Exceeding the limit temperature can permanently damage the magnet.

* Holding force was tested on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, however under parallel forces the lifting capacity is smaller. Moreover, even a slight gap {between} the magnet and the plate lowers the lifting capacity.