UMC 20x6/3x7 / N38 - cylindrical magnetic holder

Advantages and disadvantages of neodymium magnets.

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

• They do not lose strength, even after nearly 10 years – the drop in lifting capacity is only ~1% (theoretically),
• They show high resistance to demagnetization induced by presence of other magnetic fields,
• By using a smooth coating of gold, the element presents an elegant look,
• Neodymium magnets generate maximum magnetic induction on a small area, which increases force concentration,
• Through (appropriate) combination of ingredients, they can achieve high thermal resistance, enabling functioning at temperatures reaching 230°C and above...
• Thanks to versatility in shaping and the capacity to customize to individual projects,
• Key role in innovative solutions – they are used in mass storage devices, electromotive mechanisms, diagnostic systems, and multitasking production systems.
• Thanks to concentrated force, small magnets offer high operating force, in miniature format,

Disadvantages of neodymium magnets:

• They are fragile upon too strong impacts. To avoid cracks, it is worth protecting magnets using a steel holder. Such protection not only protects the magnet but also increases its resistance to damage
• We warn that neodymium magnets can reduce their power at high temperatures. To prevent this, we suggest our specialized [AH] magnets, which work effectively even at 230°C.
• Magnets exposed to a humid environment can corrode. Therefore when using outdoors, we advise using waterproof magnets made of rubber, plastic or other material resistant to moisture
• We suggest casing - magnetic mount, due to difficulties in creating threads inside the magnet and complex forms.
• Possible danger resulting from small fragments of magnets can be dangerous, in case of ingestion, which gains importance in the context of child health protection. Furthermore, small components of these devices are able to be problematic in diagnostics medical in case of swallowing.
• With large orders the cost of neodymium magnets is a challenge,

Best holding force of the magnet in ideal parameters – what contributes to it?

Holding force of 6.00 kg is a result of laboratory testing performed under the following configuration:

• with the use of a sheet made of low-carbon steel, ensuring maximum field concentration
• whose thickness equals approx. 10 mm
• with a surface free of scratches
• with zero gap (without impurities)
• during detachment in a direction perpendicular to the plane
• at ambient temperature approx. 20 degrees Celsius

Magnet lifting force in use – key factors

In practice, the real power depends on many variables, presented from crucial:

• Distance – the presence of any layer (paint, tape, air) acts as an insulator, which reduces power rapidly (even by 50% at 0.5 mm).
• Force direction – remember that the magnet has greatest strength perpendicularly. Under shear forces, the capacity drops drastically, often to levels of 20-30% of the maximum value.
• Wall thickness – the thinner the sheet, the weaker the hold. Part of the magnetic field penetrates through instead of generating force.
• Steel grade – ideal substrate is pure iron steel. Stainless steels may generate lower lifting capacity.
• Surface finish – ideal contact is possible only on smooth steel. Rough texture reduce the real contact area, weakening the magnet.
• Thermal factor – high temperature weakens pulling force. Too high temperature can permanently damage the magnet.

* Lifting capacity testing was performed on plates with a smooth surface of suitable thickness, under a perpendicular pulling force, in contrast under shearing force the load capacity is reduced by as much as fivefold. In addition, even a minimal clearance {between} the magnet’s surface and the plate decreases the lifting capacity.