RM R1 - 10000 Gs / N52 - magnetic distributor

Advantages as well as disadvantages of neodymium magnets NdFeB.

In addition to their magnetic efficiency, neodymium magnets provide the following advantages:

• They virtually do not lose strength, because even after 10 years, the performance loss is only ~1% (in laboratory conditions),
• They remain magnetized despite exposure to magnetic noise,
• Because of the lustrous layer of gold, the component looks high-end,
• They possess significant magnetic force measurable at the magnet’s surface,
• They are suitable for high-temperature applications, operating effectively at 230°C+ due to advanced heat resistance and form-specific properties,
• The ability for accurate shaping and customization to individual needs – neodymium magnets can be manufactured in many forms and dimensions, which extends the scope of their use cases,
• Key role in modern technologies – they are utilized in hard drives, electric drives, diagnostic apparatus as well as sophisticated instruments,
• Relatively small size with high magnetic force – neodymium magnets offer impressive pulling strength in tiny dimensions, which makes them ideal in compact constructions

Disadvantages of NdFeB magnets:

• They are fragile when subjected to a strong impact. If the magnets are exposed to physical collisions, we recommend in a protective case. The steel housing, in the form of a holder, protects the magnet from fracture while also reinforces its overall strength,
• Magnets lose field strength when exposed to temperatures exceeding 80°C. In most cases, this leads to irreversible field weakening (influenced by the magnet’s form). To address this, we provide [AH] models with superior thermal resistance, able to operate even at 230°C or more,
• Magnets exposed to wet conditions can oxidize. Therefore, for outdoor applications, we suggest waterproof types made of rubber,
• Limited ability to create internal holes in the magnet – the use of a mechanical support is recommended,
• Possible threat from tiny pieces may arise, in case of ingestion, which is crucial in the protection of children. It should also be noted that tiny components from these devices may hinder health screening after being swallowed,
• High unit cost – neodymium magnets are costlier than other types of magnets (e.g., ferrite), which may limit large-scale applications

Magnetic strength at its maximum – what affects it?

The given pulling force of the magnet represents the maximum force, determined in the best circumstances, namely:

• with the use of low-carbon steel plate acting as a magnetic yoke
• having a thickness of no less than 10 millimeters
• with a polished side
• with zero air gap
• in a perpendicular direction of force
• in normal thermal conditions

Key elements affecting lifting force

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

• Air gap between the magnet and the plate, because 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 measured with the use of a polished steel plate of suitable thickness (min. 20 mm), under vertically applied force, in contrast under shearing force the load capacity is reduced by as much as fivefold. In addition, even a small distance {between} the magnet and the plate decreases the lifting capacity.