UMGGZ 88x8.5 [M8] GZ / N38 - rubber magnetic holder external thread

Advantages and disadvantages of rare earth magnets.

Besides their tremendous pulling force, neodymium magnets offer the following advantages:

• They virtually do not lose strength, because even after ten years the decline in efficiency is only ~1% (in laboratory conditions),
• They are resistant to demagnetization induced by external magnetic fields,
• The use of an aesthetic layer of noble metals (nickel, gold, silver) causes the element to be more visually attractive,
• They show high magnetic induction at the operating surface, which affects their effectiveness,
• 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...
• Thanks to versatility in shaping and the ability to adapt to individual projects,
• Huge importance in future technologies – they are commonly used in magnetic memories, drive modules, advanced medical instruments, and other advanced devices.
• Thanks to efficiency per cm³, small magnets offer high operating force, occupying minimum space,

Disadvantages of neodymium magnets:

• To avoid cracks under impact, we recommend using special steel housings. Such a solution secures 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 power. Therefore, we recommend our special magnets marked [AH], which maintain stability even at temperatures up to 230°C
• They rust in a humid environment. For use outdoors we suggest using waterproof magnets e.g. in rubber, plastic
• Limited ability of creating nuts in the magnet and complex forms - recommended is casing - magnet mounting.
• Potential hazard to health – tiny shards of magnets pose a threat, in case of ingestion, which gains importance in the aspect of protecting the youngest. Additionally, small components of these magnets can complicate diagnosis medical after entering the body.
• With large orders the cost of neodymium magnets is economically unviable,

Detachment force of the magnet in optimal conditions – what affects it?

The declared magnet strength refers to the limit force, measured under ideal test conditions, namely:

• with the application of a yoke made of special test steel, ensuring maximum field concentration
• whose transverse dimension reaches at least 10 mm
• with an ground touching surface
• under conditions of ideal adhesion (metal-to-metal)
• under vertical force direction (90-degree angle)
• in temp. approx. 20°C

What influences lifting capacity in practice

Real force is affected by specific conditions, including (from most important):

• Gap between surfaces – even a fraction of a millimeter of distance (caused e.g. by veneer or dirt) diminishes the magnet efficiency, often by half at just 0.5 mm.
• Force direction – catalog parameter refers to pulling vertically. When applying parallel force, the magnet exhibits much less (typically approx. 20-30% of maximum force).
• Steel thickness – insufficiently thick sheet does not close the flux, causing part of the power to be lost to the other side.
• Metal type – different alloys attracts identically. High carbon content worsen the interaction with the magnet.
• Surface structure – the more even the surface, the larger the contact zone and stronger the hold. Unevenness acts like micro-gaps.
• Operating temperature – NdFeB sinters have a sensitivity to temperature. At higher temperatures they are weaker, and in frost gain strength (up to a certain limit).

* Lifting capacity testing was conducted on a smooth plate of suitable thickness, under perpendicular forces, in contrast under attempts to slide the magnet the load capacity is reduced by as much as 75%. Additionally, even a small distance {between} the magnet and the plate lowers the holding force.