SMZR 32x200 / N52 - magnetic separator with handle

Strengths and weaknesses of neodymium magnets.

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

• They have unchanged lifting capacity, and over nearly 10 years their performance decreases symbolically – ~1% (according to theory),
• They feature excellent resistance to magnetic field loss due to opposing magnetic fields,
• A magnet with a shiny silver surface is more attractive,
• Magnetic induction on the surface of the magnet turns out to be extremely intense,
• Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their form) at temperatures up to 230°C and above...
• Thanks to versatility in forming and the ability to modify to individual projects,
• Key role in electronics industry – they find application in mass storage devices, electromotive mechanisms, medical devices, as well as complex engineering applications.
• Thanks to their power density, small magnets offer high operating force, with minimal size,

What to avoid - cons of neodymium magnets: weaknesses and usage proposals

• At very strong impacts they can break, therefore we recommend placing them in special holders. A metal housing provides additional protection against damage, as well as increases the magnet's durability.
• NdFeB magnets demagnetize when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop of strength (a factor is the shape and dimensions of the magnet). We offer magnets specially adapted to work at temperatures up to 230°C marked [AH], which are very resistant to heat
• Magnets exposed to a humid environment can corrode. Therefore during using outdoors, we suggest using waterproof magnets made of rubber, plastic or other material resistant to moisture
• Limited possibility of producing nuts in the magnet and complex forms - recommended is a housing - magnetic holder.
• Health risk related to microscopic parts of magnets pose a threat, if swallowed, which becomes key in the aspect of protecting the youngest. Additionally, small elements of these devices can be problematic in diagnostics medical in case of swallowing.
• With large orders the cost of neodymium magnets is a challenge,

Best holding force of the magnet in ideal parameters – what contributes to it?

Holding force of 0 kg is a measurement result performed under specific, ideal conditions:

• with the contact of a yoke made of special test steel, ensuring full magnetic saturation
• with a thickness no less than 10 mm
• with an polished contact surface
• without any air gap between the magnet and steel
• under vertical application of breakaway force (90-degree angle)
• at room temperature

Practical aspects of lifting capacity – factors

Please note that the application force may be lower influenced by the following factors, in order of importance:

• Gap (between the magnet and the plate), as even a very small distance (e.g. 0.5 mm) leads to a decrease in lifting capacity by up to 50% (this also applies to varnish, corrosion or debris).
• Loading method – catalog parameter refers to detachment vertically. When applying parallel force, the magnet exhibits much less (typically approx. 20-30% of nominal force).
• Base massiveness – insufficiently thick sheet does not close the flux, causing part of the power to be escaped to the other side.
• Metal type – different alloys attracts identically. Alloy additives weaken the interaction with the magnet.
• Surface condition – ground elements ensure maximum contact, which increases force. Uneven metal reduce efficiency.
• Temperature – temperature increase causes a temporary drop of induction. It is worth remembering the maximum operating temperature for a given model.

* Lifting capacity testing was conducted on plates with a smooth surface of optimal thickness, under a perpendicular pulling force, however under parallel forces the lifting capacity is smaller. In addition, even a minimal clearance {between} the magnet’s surface and the plate reduces the holding force.