SM 32x200 [2xM8] / N52 - magnetic separator

Advantages and disadvantages of neodymium magnets NdFeB.

Besides their high retention, neodymium magnets are valued for these benefits:

• They retain their full power for almost 10 years – the drop is just ~1% (according to analyses),
• They protect against demagnetization induced by ambient magnetic influence very well,
• By applying a shiny layer of gold, the element gains a sleek look,
• They exhibit extremely high levels of magnetic induction near the outer area of the magnet,
• They are suitable for high-temperature applications, operating effectively at 230°C+ due to advanced heat resistance and form-specific properties,
• With the option for customized forming and personalized design, these magnets can be produced in multiple shapes and sizes, greatly improving engineering flexibility,
• Important function in modern technologies – they serve a purpose in hard drives, electromechanical systems, diagnostic apparatus along with technologically developed systems,
• Compactness – despite their small size, they generate strong force, making them ideal for precision applications

Disadvantages of magnetic elements:

• They are prone to breaking when subjected to a heavy impact. If the magnets are exposed to mechanical hits, we recommend in a protective case. The steel housing, in the form of a holder, protects the magnet from fracture and enhances its overall durability,
• High temperatures may significantly reduce the holding force of neodymium magnets. Typically, above 80°C, they experience permanent deterioration in performance (depending on size). To prevent this, we offer heat-resistant magnets marked [AH], capable of working up to 230°C, which makes them perfect for high-temperature use,
• Magnets exposed to moisture can corrode. Therefore, for outdoor applications, we advise waterproof types made of rubber,
• Limited ability to create internal holes in the magnet – the use of a external casing is recommended,
• Potential hazard linked to microscopic shards may arise, if ingested accidentally, which is significant in the family environments. Additionally, minuscule fragments from these magnets can complicate medical imaging if inside the body,
• Due to a complex production process, their cost is considerably higher,

Magnetic strength at its maximum – what contributes to it?

The given strength of the magnet means the optimal strength, determined in ideal conditions, specifically:

• with the use of low-carbon steel plate acting as a magnetic yoke
• with a thickness of minimum 10 mm
• with a refined outer layer
• with no separation
• with vertical force applied
• in normal thermal conditions

Practical aspects of lifting capacity – factors

In practice, the holding capacity of a magnet is affected by the following aspects, arranged from the most important to the least relevant:

• Air gap between the magnet and the plate, since even a very small distance (e.g. 0.5 mm) causes a drop in lifting force of up to 50%.
• Direction of applied force, because the maximum lifting capacity is achieved under perpendicular application. The force required to slide the magnet along the plate is usually several times lower.
• Thickness of the plate, as a plate that is too thin causes part of the magnetic flux not to be used and to remain wasted in the air.
• Material of the plate, because higher carbon content lowers holding force, while higher iron content increases it. The best choice is steel with high magnetic permeability and high saturation induction.
• Surface of the plate, because the more smooth and polished it is, the better the contact and consequently the greater the magnetic saturation.
• Operating temperature, since all permanent magnets have a negative temperature coefficient. This means that at high temperatures they are weaker, while at sub-zero temperatures they become slightly stronger.

* Lifting capacity was determined by applying a steel plate with a smooth surface of optimal thickness (min. 20 mm), under vertically applied force, whereas under parallel forces the load capacity is reduced by as much as 5 times. In addition, even a slight gap {between} the magnet and the plate decreases the load capacity.