SM 25x225 [2xM8] / N52 - magnetic separator

Pros as well as cons of NdFeB magnets.

Apart from their notable magnetism, neodymium magnets have these key benefits:

• Their strength is durable, and after approximately ten years it decreases only by ~1% (theoretically),
• They possess excellent resistance to magnetic field loss due to external magnetic sources,
• By using a reflective coating of nickel, the element acquires an proper look,
• They are known for high magnetic induction at the operating surface, making them more effective,
• Through (appropriate) combination of ingredients, they can achieve high thermal strength, allowing for functioning at temperatures approaching 230°C and above...
• Thanks to modularity in constructing and the capacity to adapt to unusual requirements,
• Wide application in modern technologies – they serve a role in computer drives, electric drive systems, precision medical tools, and complex engineering applications.
• Thanks to their power density, small magnets offer high operating force, occupying minimum space,

Cons of neodymium magnets and ways of using them

• To avoid cracks upon strong impacts, we suggest using special steel holders. Such a solution protects the magnet and simultaneously increases its durability.
• We warn that neodymium magnets can lose their power at high temperatures. To prevent this, we advise our specialized [AH] magnets, which work effectively even at 230°C.
• When exposed to humidity, magnets usually rust. To use them in conditions outside, it is recommended to use protective magnets, such as those in rubber or plastics, which secure oxidation as well as corrosion.
• Due to limitations in creating threads and complicated forms in magnets, we recommend using a housing - magnetic mount.
• Possible danger related to microscopic parts of magnets pose a threat, if swallowed, which gains importance in the aspect of protecting the youngest. Additionally, small components of these products are able to complicate diagnosis medical in case of swallowing.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

Breakaway strength of the magnet in ideal conditions – what affects it?

The force parameter is a result of laboratory testing conducted under specific, ideal conditions:

• with the use of a sheet made of low-carbon steel, ensuring full magnetic saturation
• with a cross-section minimum 10 mm
• characterized by smoothness
• under conditions of gap-free contact (metal-to-metal)
• for force acting at a right angle (pull-off, not shear)
• at room temperature

Key elements affecting lifting force

In real-world applications, the actual lifting capacity is determined by several key aspects, ranked from most significant:

• Gap between surfaces – even a fraction of a millimeter of separation (caused e.g. by varnish or dirt) diminishes the magnet efficiency, often by half at just 0.5 mm.
• Pull-off angle – remember that the magnet holds strongest perpendicularly. Under shear forces, the holding force drops significantly, often to levels of 20-30% of the maximum value.
• Wall thickness – the thinner the sheet, the weaker the hold. Part of the magnetic field passes through the material instead of converting into lifting capacity.
• Metal type – different alloys attracts identically. Alloy additives weaken the attraction effect.
• Surface quality – the smoother and more polished the plate, the larger the contact zone and stronger the hold. Roughness acts like micro-gaps.
• Temperature – temperature increase causes a temporary drop of force. Check the thermal limit for a given model.

* Lifting capacity testing was conducted on plates with a smooth surface of optimal thickness, under a perpendicular pulling force, in contrast under parallel forces the holding force is lower. In addition, even a small distance {between} the magnet’s surface and the plate reduces the holding force.