SM 25x200 [2xM8] / N52 - magnetic separator

Pros as well as cons of rare earth magnets.

In addition to their long-term stability, neodymium magnets provide the following advantages:

• Their strength is durable, and after approximately ten years it decreases only by ~1% (according to research),
• They show high resistance to demagnetization induced by presence of other magnetic fields,
• The use of an shiny finish of noble metals (nickel, gold, silver) causes the element to look better,
• Neodymium magnets create maximum magnetic induction on a small surface, which ensures high operational effectiveness,
• Through (adequate) combination of ingredients, they can achieve high thermal resistance, allowing for functioning at temperatures approaching 230°C and above...
• Thanks to flexibility in designing and the ability to adapt to individual projects,
• Huge importance in electronics industry – they are utilized in data components, electric motors, precision medical tools, and technologically advanced constructions.
• Relatively small size with high pulling force – neodymium magnets offer high power in compact dimensions, which makes them useful in small systems

Cons of neodymium magnets: tips and applications.

• They are prone to damage upon heavy impacts. To avoid cracks, it is worth securing magnets in a protective case. Such protection not only shields the magnet but also increases its resistance to damage
• Neodymium magnets lose their power 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 durability even at temperatures up to 230°C
• They oxidize in a humid environment - during use outdoors we advise using waterproof magnets e.g. in rubber, plastic
• We suggest cover - magnetic mechanism, due to difficulties in realizing threads inside the magnet and complex shapes.
• Potential hazard related to microscopic parts of magnets are risky, if swallowed, which becomes key in the context of child health protection. Additionally, tiny parts of these magnets are able to disrupt the diagnostic process medical in case of swallowing.
• Due to complex production process, their price is relatively high,

Maximum lifting force for a neodymium magnet – what affects it?

Holding force of 0 kg is a measurement result executed under standard conditions:

• using a base made of mild steel, serving as a magnetic yoke
• with a thickness no less than 10 mm
• with a plane cleaned and smooth
• without any air gap between the magnet and steel
• for force acting at a right angle (pull-off, not shear)
• at ambient temperature approx. 20 degrees Celsius

Magnet lifting force in use – key factors

In real-world applications, the real power depends on a number of factors, listed from the most important:

• Clearance – existence of foreign body (paint, tape, air) acts as an insulator, which reduces capacity rapidly (even by 50% at 0.5 mm).
• Load vector – maximum parameter is obtained only during pulling at a 90° angle. The force required to slide of the magnet along the plate is standardly many times lower (approx. 1/5 of the lifting capacity).
• Steel thickness – too thin plate causes magnetic saturation, causing part of the power to be escaped into the air.
• Steel grade – ideal substrate is pure iron steel. Stainless steels may attract less.
• Smoothness – ideal contact is possible only on polished steel. Rough texture reduce the real contact area, weakening the magnet.
• Thermal factor – hot environment weakens magnetic field. Too high temperature can permanently demagnetize the magnet.

* Lifting capacity testing was performed on a smooth plate of optimal thickness, under a perpendicular pulling force, whereas under parallel forces the lifting capacity is smaller. Additionally, even a minimal clearance {between} the magnet and the plate reduces the load capacity.