MW 5x15 / N38 - cylindrical magnet

Strengths and weaknesses of neodymium magnets.

Besides their high retention, neodymium magnets are valued for these benefits:

• They do not lose strength, even over around 10 years – the reduction in power is only ~1% (based on measurements),
• Neodymium magnets are highly resistant to demagnetization caused by external interference,
• In other words, due to the metallic layer of nickel, the element looks attractive,
• The surface of neodymium magnets generates a strong magnetic field – this is a key feature,
• Neodymium magnets are characterized by very high magnetic induction on the magnet surface and are able to act (depending on the shape) even at a temperature of 230°C or more...
• Thanks to the possibility of precise forming and customization to individualized solutions, neodymium magnets can be modeled in a wide range of geometric configurations, which makes them more universal,
• Significant place in advanced technology sectors – they are utilized in hard drives, electromotive mechanisms, medical devices, as well as industrial machines.
• Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in tiny dimensions, which enables their usage in miniature devices

Disadvantages of neodymium magnets:

• At very strong impacts they can break, therefore we recommend placing them in steel cases. A metal housing provides additional protection against damage and increases the magnet's durability.
• Neodymium magnets lose 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
• Magnets exposed to a humid environment can corrode. 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 threads and complex forms in magnets, we recommend using cover - magnetic holder.
• Health risk resulting from small fragments of magnets pose a threat, in case of ingestion, which gains importance in the context of child safety. Furthermore, small elements of these products can be problematic in diagnostics medical when they are in the body.
• With mass production the cost of neodymium magnets is economically unviable,

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

Magnet power is the result of a measurement for the most favorable conditions, taking into account:

• with the application of a sheet made of low-carbon steel, ensuring maximum field concentration
• with a thickness no less than 10 mm
• with a plane free of scratches
• under conditions of ideal adhesion (surface-to-surface)
• under axial force direction (90-degree angle)
• at room temperature

Lifting capacity in real conditions – factors

Please note that the working load will differ influenced by the following factors, in order of importance:

• Distance (betwixt the magnet and the plate), because even a very small clearance (e.g. 0.5 mm) can cause a reduction in lifting capacity by up to 50% (this also applies to varnish, rust or dirt).
• Force direction – catalog parameter refers to detachment vertically. When slipping, the magnet exhibits significantly lower power (typically approx. 20-30% of nominal force).
• Plate thickness – too thin steel causes magnetic saturation, causing part of the flux to be wasted into the air.
• Metal type – not every steel attracts identically. High carbon content weaken the interaction with the magnet.
• Plate texture – smooth surfaces guarantee perfect abutment, which increases field saturation. Uneven metal weaken the grip.
• Thermal factor – high temperature weakens magnetic field. Exceeding the limit temperature can permanently demagnetize the magnet.

* Holding force was checked on a smooth steel plate of 20 mm thickness, when a perpendicular force was applied, in contrast under parallel forces the holding force is lower. Additionally, even a slight gap {between} the magnet and the plate reduces the lifting capacity.