SMZR 32x125 / N52 - magnetic separator with handle

Pros as well as cons of NdFeB magnets.

In addition to their pulling strength, neodymium magnets provide the following advantages:

• They do not lose magnetism, even over around 10 years – the drop in lifting capacity is only ~1% (theoretically),
• Magnets very well protect themselves against loss of magnetization caused by foreign field sources,
• A magnet with a smooth silver surface is more attractive,
• The surface of neodymium magnets generates a intense magnetic field – this is one of their assets,
• Neodymium magnets are characterized by very high magnetic induction on the magnet surface and can function (depending on the form) even at a temperature of 230°C or more...
• Possibility of precise modeling as well as adjusting to atypical conditions,
• Versatile presence in future technologies – they find application in hard drives, electromotive mechanisms, precision medical tools, and other advanced devices.
• Relatively small size with high pulling force – neodymium magnets offer high power in compact dimensions, which enables their usage in compact constructions

Disadvantages of neodymium magnets:

• They are prone to damage upon too strong impacts. To avoid cracks, it is worth protecting magnets in special housings. Such protection not only shields the magnet but also improves its resistance to damage
• 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
• When exposed to humidity, magnets start to rust. To use them in conditions outside, it is recommended to use protective magnets, such as magnets in rubber or plastics, which secure oxidation and corrosion.
• Due to limitations in producing nuts and complicated shapes in magnets, we recommend using a housing - magnetic mechanism.
• Possible danger related to microscopic parts of magnets are risky, when accidentally swallowed, which becomes key in the context of child safety. Furthermore, small elements of these products can disrupt the diagnostic process medical when they are in the body.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

Highest magnetic holding force – what contributes to it?

Holding force of 0 kg is a measurement result conducted under the following configuration:

• with the use of a sheet made of low-carbon steel, guaranteeing maximum field concentration
• whose thickness is min. 10 mm
• with an ideally smooth touching surface
• without the slightest insulating layer between the magnet and steel
• under perpendicular force direction (90-degree angle)
• at temperature approx. 20 degrees Celsius

Magnet lifting force in use – key factors

During everyday use, the actual holding force results from a number of factors, ranked from most significant:

• Distance (betwixt the magnet and the metal), since even a tiny distance (e.g. 0.5 mm) can cause a reduction in lifting capacity by up to 50% (this also applies to paint, rust or debris).
• Force direction – catalog parameter refers to detachment vertically. When slipping, the magnet exhibits significantly lower power (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).
• Material type – ideal substrate is pure iron steel. Hardened steels may generate lower lifting capacity.
• Surface quality – the more even the surface, the larger the contact zone and stronger the hold. Roughness creates an air distance.
• Thermal factor – hot environment weakens magnetic field. Too high temperature can permanently damage the magnet.

* Lifting capacity testing was performed on plates with a smooth surface of optimal thickness, under perpendicular forces, in contrast under parallel forces the holding force is lower. Additionally, even a minimal clearance {between} the magnet’s surface and the plate reduces the load capacity.