SM 32x325 [2xM8] / N52 - magnetic separator

Advantages as well as disadvantages of neodymium magnets.

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

• They do not lose power, even during nearly 10 years – the reduction in strength is only ~1% (according to tests),
• They are extremely resistant to demagnetization induced by presence of other magnetic fields,
• By using a reflective coating of nickel, the element presents an elegant look,
• Neodymium magnets ensure maximum magnetic induction on a contact point, which allows for strong attraction,
• Neodymium magnets are characterized by very high magnetic induction on the magnet surface and can function (depending on the shape) even at a temperature of 230°C or more...
• Possibility of precise creating as well as optimizing to atypical requirements,
• Significant place in modern industrial fields – they are used in data components, drive modules, advanced medical instruments, also multitasking production systems.
• Compactness – despite small sizes they provide effective action, making them ideal for precision applications

Disadvantages of neodymium magnets:

• Susceptibility to cracking is one of their disadvantages. Upon intense impact they can fracture. We recommend keeping them in a special holder, which not only secures them against impacts but also increases their durability
• Neodymium magnets lose their force under the influence of heating. As soon as 80°C is exceeded, many of them start losing their force. Therefore, we recommend our special magnets marked [AH], which maintain stability even at temperatures up to 230°C
• They oxidize in a humid environment - during use outdoors we suggest using waterproof magnets e.g. in rubber, plastic
• Due to limitations in creating threads and complicated forms in magnets, we propose using cover - magnetic mount.
• Potential hazard to health – tiny shards of magnets are risky, in case of ingestion, which becomes key in the context of child safety. It is also worth noting that tiny parts of these magnets can complicate diagnosis medical after entering the body.
• Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Maximum magnetic pulling force – what it depends on?

Magnet power was defined for the most favorable conditions, taking into account:

• using a sheet made of low-carbon steel, functioning as a circuit closing element
• whose thickness is min. 10 mm
• with a plane perfectly flat
• with total lack of distance (without impurities)
• for force acting at a right angle (in the magnet axis)
• at conditions approx. 20°C

Practical lifting capacity: influencing factors

Holding efficiency is influenced by specific conditions, mainly (from priority):

• Gap between surfaces – every millimeter of distance (caused e.g. by varnish or unevenness) significantly weakens the magnet efficiency, often by half at just 0.5 mm.
• Angle of force application – maximum parameter is available only during perpendicular pulling. The shear force of the magnet along the surface is typically many times smaller (approx. 1/5 of the lifting capacity).
• Element thickness – to utilize 100% power, the steel must be adequately massive. Paper-thin metal restricts the lifting capacity (the magnet "punches through" it).
• Plate material – mild steel attracts best. Alloy admixtures decrease magnetic properties and lifting capacity.
• Smoothness – full contact is possible only on smooth steel. Any scratches and bumps reduce the real contact area, reducing force.
• Temperature influence – hot environment weakens magnetic field. Exceeding the limit temperature can permanently demagnetize the magnet.

* Holding force was checked on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, however under parallel forces the holding force is lower. Moreover, even a slight gap {between} the magnet and the plate lowers the holding force.