SM 32x425 [2xM8] / N52 - magnetic separator

Advantages and disadvantages of rare earth magnets.

Besides their magnetic performance, neodymium magnets are valued for these benefits:

• Their strength is durable, and after approximately ten years it drops only by ~1% (according to research),
• They are extremely resistant to demagnetization induced by external disturbances,
• Thanks to the elegant finish, the layer of nickel, gold-plated, or silver gives an clean appearance,
• The surface of neodymium magnets generates a concentrated magnetic field – this is a key feature,
• Through (appropriate) combination of ingredients, they can achieve high thermal resistance, allowing for action at temperatures reaching 230°C and above...
• Thanks to versatility in forming and the ability to customize to complex applications,
• Key role in electronics industry – they find application in data components, drive modules, medical equipment, also other advanced devices.
• Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in tiny dimensions, which enables their usage in compact constructions

Disadvantages of NdFeB magnets:

• To avoid cracks upon strong impacts, we suggest using special steel holders. Such a solution secures the magnet and simultaneously increases its durability.
• We warn that neodymium magnets can lose their strength at high temperatures. To prevent this, we recommend 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 magnets in rubber or plastics, which secure oxidation as well as corrosion.
• Due to limitations in producing threads and complicated forms in magnets, we recommend using cover - magnetic mount.
• Potential hazard to health – tiny shards of magnets can be dangerous, if swallowed, which gains importance in the aspect of protecting the youngest. Additionally, tiny parts of these products are able to disrupt the diagnostic process medical in case of swallowing.
• High unit price – neodymium magnets are more expensive than other types of magnets (e.g. ferrite), which can limit application in large quantities

Maximum holding power of the magnet – what it depends on?

Magnet power was determined for optimal configuration, taking into account:

• using a base made of low-carbon steel, functioning as a circuit closing element
• with a thickness of at least 10 mm
• with a surface free of scratches
• without the slightest insulating layer between the magnet and steel
• during pulling in a direction perpendicular to the plane
• in neutral thermal conditions

Practical lifting capacity: influencing factors

Holding efficiency impacted by working environment parameters, such as (from most important):

• Gap (betwixt the magnet and the metal), since even a microscopic distance (e.g. 0.5 mm) leads to a drastic drop in lifting capacity by up to 50% (this also applies to varnish, corrosion or debris).
• Pull-off angle – remember that the magnet has greatest strength perpendicularly. Under sliding down, the capacity drops drastically, often to levels of 20-30% of the nominal value.
• Substrate thickness – for full efficiency, the steel must be adequately massive. Thin sheet limits the lifting capacity (the magnet "punches through" it).
• Material composition – different alloys attracts identically. High carbon content weaken the attraction effect.
• Base smoothness – the more even the plate, the larger the contact zone and higher the lifting capacity. Unevenness creates an air distance.
• Thermal environment – temperature increase results in weakening of force. Check the maximum operating temperature for a given model.

* Lifting capacity was measured using a polished steel plate of optimal thickness (min. 20 mm), under perpendicular detachment force, in contrast under attempts to slide the magnet the lifting capacity is smaller. Additionally, even a minimal clearance {between} the magnet and the plate reduces the load capacity.