UMGZ 16x13x5 [M4] GZ / N38 - magnetic holder external thread

Advantages and disadvantages of NdFeB magnets.

In addition to their magnetic efficiency, neodymium magnets provide the following advantages:

• They virtually do not lose strength, because even after ten years the performance loss is only ~1% (in laboratory conditions),
• They are extremely resistant to demagnetization induced by presence of other magnetic fields,
• In other words, due to the shiny layer of nickel, the element gains visual value,
• They show high magnetic induction at the operating surface, which improves attraction properties,
• Thanks to resistance to high temperature, they are capable of working (depending on the shape) even at temperatures up to 230°C and higher...
• Possibility of custom machining and optimizing to complex requirements,
• Huge importance in future technologies – they are used in HDD drives, motor assemblies, medical equipment, also multitasking production systems.
• Thanks to their power density, small magnets offer high operating force, occupying minimum space,

Disadvantages of NdFeB magnets:

• To avoid cracks upon strong impacts, we suggest using special steel holders. Such a solution secures the magnet and simultaneously improves its durability.
• We warn that neodymium magnets can lose their power at high temperatures. To prevent this, we advise our specialized [AH] magnets, which work effectively even at 230°C.
• Magnets exposed to a humid environment can rust. Therefore during using outdoors, we suggest using water-impermeable magnets made of rubber, plastic or other material resistant to moisture
• Due to limitations in producing nuts and complex forms in magnets, we propose using cover - magnetic holder.
• Possible danger to health – tiny shards of magnets pose a threat, when accidentally swallowed, which becomes key in the context of child safety. It is also worth noting that small elements of these devices can disrupt the diagnostic process medical when they are in the body.
• High unit price – neodymium magnets are more expensive than other types of magnets (e.g. ferrite), which hinders application in large quantities

Breakaway strength of the magnet in ideal conditions – what it depends on?

Magnet power was defined for optimal configuration, taking into account:

• on a plate made of structural steel, effectively closing the magnetic flux
• with a thickness no less than 10 mm
• with a surface perfectly flat
• without any insulating layer between the magnet and steel
• during detachment in a direction perpendicular to the mounting surface
• at conditions approx. 20°C

Impact of factors on magnetic holding capacity in practice

It is worth knowing that the working load may be lower depending on the following factors, starting with the most relevant:

• Gap between surfaces – every millimeter of distance (caused e.g. by varnish or dirt) drastically reduces the magnet efficiency, often by half at just 0.5 mm.
• Angle of force application – highest force is available only during pulling at a 90° angle. The shear force of the magnet along the surface is typically many times smaller (approx. 1/5 of the lifting capacity).
• Metal thickness – the thinner the sheet, the weaker the hold. Part of the magnetic field passes through the material instead of converting into lifting capacity.
• Material type – ideal substrate is high-permeability steel. Hardened steels may generate lower lifting capacity.
• Smoothness – ideal contact is obtained only on polished steel. Rough texture reduce the real contact area, weakening the magnet.
• Temperature influence – hot environment reduces magnetic field. Too high temperature can permanently damage the magnet.

* Holding force was checked on the plate surface of 20 mm thickness, when the force acted perpendicularly, whereas under attempts to slide the magnet the load capacity is reduced by as much as 5 times. In addition, even a slight gap {between} the magnet and the plate reduces the holding force.