UMP 29x10 [M5] GW - search holder

Pros and cons of neodymium magnets.

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

• They have constant strength, and over more than 10 years their performance decreases symbolically – ~1% (according to theory),
• Magnets effectively protect themselves against loss of magnetization caused by foreign field sources,
• A magnet with a smooth gold surface is more attractive,
• Neodymium magnets deliver maximum magnetic induction on a small area, which ensures high operational effectiveness,
• Neodymium magnets are characterized by extremely high magnetic induction on the magnet surface and are able to act (depending on the form) even at a temperature of 230°C or more...
• Possibility of precise machining and adapting to concrete conditions,
• Huge importance in high-tech industry – they serve a role in HDD drives, brushless drives, advanced medical instruments, and technologically advanced constructions.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in small dimensions, which enables their usage in small systems

Disadvantages of neodymium magnets:

• At very strong impacts they can break, therefore we advise placing them in special holders. A metal housing provides additional protection against damage and increases the magnet's durability.
• When exposed to high temperature, neodymium magnets experience a drop in power. Often, when the temperature exceeds 80°C, their strength decreases (depending on the size and shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
• When exposed to humidity, magnets usually rust. For applications outside, it is recommended to use protective magnets, such as those in rubber or plastics, which prevent oxidation and corrosion.
• We recommend a housing - magnetic mount, due to difficulties in creating threads inside the magnet and complicated shapes.
• Health risk related to microscopic parts of magnets can be dangerous, if swallowed, which gains importance in the aspect of protecting the youngest. Additionally, small components of these devices can disrupt the diagnostic process medical after entering the body.
• Due to neodymium price, their price exceeds standard values,

Magnetic strength at its maximum – what it depends on?

Information about lifting capacity was determined for optimal configuration, taking into account:

• with the application of a sheet made of low-carbon steel, ensuring full magnetic saturation
• whose transverse dimension equals approx. 10 mm
• with a plane perfectly flat
• under conditions of gap-free contact (metal-to-metal)
• during pulling in a direction vertical to the plane
• at temperature approx. 20 degrees Celsius

Lifting capacity in practice – influencing factors

Please note that the magnet holding may be lower influenced by elements below, starting with the most relevant:

• Air gap (betwixt the magnet and the metal), because even a tiny distance (e.g. 0.5 mm) can cause a reduction in lifting capacity by up to 50% (this also applies to varnish, corrosion or debris).
• Loading method – declared lifting capacity refers to pulling vertically. When slipping, the magnet holds much less (typically approx. 20-30% of maximum force).
• Substrate thickness – for full efficiency, the steel must be sufficiently thick. Thin sheet limits the lifting capacity (the magnet "punches through" it).
• Plate material – low-carbon steel gives the best results. Higher carbon content decrease magnetic properties and holding force.
• Surface finish – full contact is obtained only on smooth steel. Rough texture reduce the real contact area, weakening the magnet.
• Thermal environment – temperature increase causes a temporary drop of force. Check the maximum operating temperature for a given model.

* Lifting capacity testing was carried out on plates with a smooth surface of optimal thickness, under perpendicular forces, however under shearing force the holding force is lower. In addition, even a slight gap {between} the magnet and the plate lowers the lifting capacity.