NCM 40x13.5x5 / N38 - channel magnetic holder

Pros and cons of rare earth magnets.

Besides their tremendous strength, neodymium magnets offer the following advantages:

• They virtually do not lose strength, because even after 10 years the decline in efficiency is only ~1% (in laboratory conditions),
• Neodymium magnets are distinguished by exceptionally resistant to magnetic field loss caused by external interference,
• A magnet with a shiny silver surface looks better,
• Magnets are characterized by exceptionally strong magnetic induction on the outer layer,
• Neodymium magnets are characterized by extremely high magnetic induction on the magnet surface and can work (depending on the form) even at a temperature of 230°C or more...
• Possibility of detailed creating as well as optimizing to complex conditions,
• Huge importance in modern technologies – they are used in data components, brushless drives, medical devices, as well as other advanced devices.
• Compactness – despite small sizes they provide effective action, making them ideal for precision applications

Disadvantages of neodymium magnets:

• Brittleness is one of their disadvantages. Upon strong impact they can fracture. We recommend keeping them in a strong case, which not only protects them against impacts but also raises their durability
• Neodymium magnets lose their force 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
• 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 protecting against moisture
• Limited ability of making threads in the magnet and complicated forms - recommended is cover - mounting mechanism.
• Health risk related to microscopic parts of magnets can be dangerous, when accidentally swallowed, which becomes key in the context of child safety. Furthermore, small elements of these devices are able to 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 can limit application in large quantities

Maximum lifting capacity of the magnet – what contributes to it?

The load parameter shown concerns the maximum value, obtained under ideal test conditions, specifically:

• on a base made of structural steel, optimally conducting the magnetic field
• whose thickness reaches at least 10 mm
• with a surface perfectly flat
• without any air gap between the magnet and steel
• during pulling in a direction vertical to the plane
• in neutral thermal conditions

Practical lifting capacity: influencing factors

Please note that the application force may be lower depending on elements below, in order of importance:

• Distance (betwixt the magnet and the plate), since even a very small clearance (e.g. 0.5 mm) leads to a reduction in force by up to 50% (this also applies to paint, corrosion or debris).
• Loading method – catalog parameter refers to detachment vertically. When applying parallel force, the magnet holds significantly lower power (often approx. 20-30% of nominal force).
• Metal thickness – the thinner the sheet, the weaker the hold. Magnetic flux penetrates through instead of converting into lifting capacity.
• Material type – the best choice is high-permeability steel. Hardened steels may attract less.
• Plate texture – ground elements guarantee perfect abutment, which increases field saturation. Uneven metal weaken the grip.
• Temperature influence – high temperature reduces magnetic field. Too high temperature can permanently damage the magnet.

* Holding force was checked on the plate surface of 20 mm thickness, when a perpendicular force was applied, whereas under parallel forces the holding force is lower. In addition, even a small distance {between} the magnet and the plate reduces the load capacity.