AM ucho [M8] - magnetic accessories

Pros and cons of NdFeB magnets.

Besides their durability, neodymium magnets are valued for these benefits:

• Their magnetic field remains stable, and after around 10 years it drops only by ~1% (according to research),
• They do not lose their magnetic properties even under close interference source,
• The use of an metallic finish of noble metals (nickel, gold, silver) causes the element to be more visually attractive,
• Neodymium magnets create maximum magnetic induction on a contact point, which ensures high operational effectiveness,
• Thanks to resistance to high temperature, they are able to function (depending on the shape) even at temperatures up to 230°C and higher...
• Considering the possibility of precise shaping and customization to individualized needs, magnetic components can be created in a variety of shapes and sizes, which amplifies use scope,
• Wide application in innovative solutions – they serve a role in hard drives, electric drive systems, advanced medical instruments, and complex engineering applications.
• Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications

Characteristics of disadvantages of neodymium magnets and ways of using them

• To avoid cracks under impact, we suggest using special steel housings. Such a solution protects the magnet and simultaneously improves its durability.
• Neodymium magnets decrease their strength under the influence of heating. As soon as 80°C is exceeded, many of them start losing their force. Therefore, we recommend our special magnets marked [AH], which maintain stability even at temperatures up to 230°C
• They oxidize in a humid environment. For use outdoors we recommend using waterproof magnets e.g. in rubber, plastic
• We suggest a housing - magnetic mechanism, due to difficulties in producing threads inside the magnet and complex forms.
• Health risk resulting from small fragments of magnets are risky, if swallowed, which is particularly important in the context of child health protection. It is also worth noting that small components of these devices are able to complicate diagnosis medical after entering the body.
• Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Maximum holding power of the magnet – what contributes to it?

Information about lifting capacity is the result of a measurement for the most favorable conditions, assuming:

• on a base made of mild steel, perfectly concentrating the magnetic flux
• whose thickness reaches at least 10 mm
• with an polished touching surface
• without the slightest clearance between the magnet and steel
• for force acting at a right angle (in the magnet axis)
• at standard ambient temperature

Key elements affecting lifting force

In practice, the actual lifting capacity depends on a number of factors, ranked from the most important:

• Gap (between the magnet and the metal), since even a very small clearance (e.g. 0.5 mm) can cause a drastic drop in force by up to 50% (this also applies to varnish, rust or dirt).
• Direction of force – highest force is reached only during pulling at a 90° angle. The force required to slide of the magnet along the surface is standardly several times lower (approx. 1/5 of the lifting capacity).
• Element thickness – for full efficiency, the steel must be sufficiently thick. Paper-thin metal limits the attraction force (the magnet "punches through" it).
• Chemical composition of the base – low-carbon steel attracts best. Higher carbon content decrease magnetic permeability and lifting capacity.
• Smoothness – full contact is possible only on polished steel. Any scratches and bumps reduce the real contact area, reducing force.
• Temperature – temperature increase causes a temporary drop of induction. Check the thermal limit for a given model.

* Lifting capacity was assessed with the use of a polished steel plate of suitable thickness (min. 20 mm), under vertically applied force, however under parallel forces the lifting capacity is smaller. Additionally, even a small distance {between} the magnet’s surface and the plate reduces the holding force.