SM 25x125 [2xM8] / N52 - magnetic separator

Advantages and disadvantages of NdFeB magnets.

Besides their remarkable strength, neodymium magnets offer the following advantages:

• They do not lose strength, even after around ten years – the reduction in power is only ~1% (based on measurements),
• They are extremely resistant to demagnetization induced by external disturbances,
• The use of an elegant layer of noble metals (nickel, gold, silver) causes the element to present itself better,
• Magnets have excellent magnetic induction on the outer side,
• Through (adequate) combination of ingredients, they can achieve high thermal strength, enabling action at temperatures approaching 230°C and above...
• Thanks to the option of accurate forming and adaptation to individualized requirements, NdFeB magnets can be modeled in a variety of forms and dimensions, which expands the range of possible applications,
• Fundamental importance in innovative solutions – they serve a role in data components, brushless drives, advanced medical instruments, and complex engineering applications.
• Thanks to efficiency per cm³, small magnets offer high operating force, in miniature format,

Problematic aspects of neodymium magnets: tips and applications.

• Brittleness is one of their disadvantages. Upon strong impact they can break. We recommend keeping them in a steel housing, which not only protects them against impacts but also increases their durability
• We warn that neodymium magnets can reduce their power at high temperatures. To prevent this, we suggest our specialized [AH] magnets, which work effectively even at 230°C.
• Magnets exposed to a humid environment can rust. Therefore while using outdoors, we recommend using waterproof magnets made of rubber, plastic or other material resistant to moisture
• Limited possibility of producing nuts in the magnet and complicated shapes - preferred is cover - magnetic holder.
• Possible danger to health – tiny shards of magnets pose a threat, in case of ingestion, which is particularly important in the context of child health protection. Furthermore, tiny parts of these devices are able to disrupt the diagnostic process medical after entering the body.
• Due to expensive raw materials, their price is relatively high,

Detachment force of the magnet in optimal conditions – what it depends on?

Information about lifting capacity is the result of a measurement for the most favorable conditions, including:

• with the application of a sheet made of low-carbon steel, guaranteeing full magnetic saturation
• possessing a thickness of min. 10 mm to ensure full flux closure
• with an ground touching surface
• under conditions of ideal adhesion (surface-to-surface)
• under vertical force vector (90-degree angle)
• in stable room temperature

Determinants of practical lifting force of a magnet

In real-world applications, the real power is determined by several key aspects, listed from crucial:

• Clearance – the presence of any layer (paint, dirt, air) interrupts the magnetic circuit, which lowers power steeply (even by 50% at 0.5 mm).
• Force direction – catalog parameter refers to detachment vertically. When applying parallel force, the magnet holds significantly lower power (typically approx. 20-30% of maximum force).
• Substrate thickness – for full efficiency, the steel must be sufficiently thick. Paper-thin metal restricts the lifting capacity (the magnet "punches through" it).
• Steel grade – the best choice is high-permeability steel. Hardened steels may have worse magnetic properties.
• Smoothness – ideal contact is possible only on smooth steel. Rough texture reduce the real contact area, weakening the magnet.
• Thermal factor – high temperature reduces magnetic field. Too high temperature can permanently damage the magnet.

* Holding force was tested on a smooth steel plate of 20 mm thickness, when a perpendicular force was applied, whereas under parallel forces the holding force is lower. In addition, even a small distance {between} the magnet and the plate reduces the load capacity.