SM 25x325 [2xM8] / N42 - magnetic separator

Pros as well as cons of neodymium magnets.

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

• They retain attractive force for almost 10 years – the loss is just ~1% (according to analyses),
• They show high resistance to demagnetization induced by external magnetic fields,
• By applying a reflective coating of silver, the element presents an elegant look,
• Neodymium magnets create maximum magnetic induction on a small area, which ensures high operational effectiveness,
• 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...
• In view of the potential of flexible shaping and adaptation to individualized projects, NdFeB magnets can be manufactured in a variety of geometric configurations, which makes them more universal,
• Versatile presence in advanced technology sectors – they are used in computer drives, drive modules, advanced medical instruments, as well as industrial machines.
• Thanks to efficiency per cm³, small magnets offer high operating force, occupying minimum space,

Drawbacks and weaknesses of neodymium magnets and proposals for their use:

• They are fragile upon too strong impacts. To avoid cracks, it is worth protecting magnets in a protective case. Such protection not only protects the magnet but also improves its resistance to damage
• When exposed to high temperature, neodymium magnets experience a drop in force. Often, when the temperature exceeds 80°C, their strength decreases (depending on the size, as well as shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
• When exposed to humidity, magnets start to 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 producing nuts and complicated forms in magnets, we recommend using casing - magnetic mount.
• Possible danger related to microscopic parts of magnets can be dangerous, in case of ingestion, which becomes key in the context of child health protection. Additionally, small components of these products are able to disrupt the diagnostic process medical after entering the body.
• Due to complex production process, their price is higher than average,

Optimal lifting capacity of a neodymium magnet – what affects it?

Information about lifting capacity was defined for the most favorable conditions, taking into account:

• using a base made of low-carbon steel, serving as a ideal flux conductor
• with a thickness of at least 10 mm
• with a plane perfectly flat
• with total lack of distance (without impurities)
• for force applied at a right angle (in the magnet axis)
• at ambient temperature room level

Magnet lifting force in use – key factors

In practice, the actual lifting capacity depends on many variables, listed from crucial:

• Distance – existence of any layer (rust, dirt, air) acts as an insulator, which lowers power steeply (even by 50% at 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 nominal value.
• Substrate thickness – to utilize 100% power, the steel must be sufficiently thick. Paper-thin metal restricts the attraction force (the magnet "punches through" it).
• Chemical composition of the base – low-carbon steel attracts best. Alloy admixtures decrease magnetic permeability and holding force.
• Plate texture – smooth surfaces guarantee perfect abutment, which increases field saturation. Uneven metal reduce efficiency.
• Thermal environment – heating the magnet causes a temporary drop of force. It is worth remembering the maximum operating temperature for a given model.

* Holding force was measured on a smooth steel plate of 20 mm thickness, when a perpendicular force was applied, in contrast under parallel forces the load capacity is reduced by as much as 5 times. In addition, even a minimal clearance {between} the magnet and the plate reduces the lifting capacity.