RM R2 - 13000 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:

• Their power is durable, and after approximately 10 years, it drops only by ~1% (according to research),
• They protect against demagnetization induced by surrounding magnetic fields remarkably well,
• By applying a reflective layer of nickel, the element gains a clean look,
• They possess strong magnetic force measurable at the magnet’s surface,
• Thanks to their enhanced temperature resistance, they can operate (depending on the form) even at temperatures up to 230°C or more,
• The ability for precise shaping or customization to specific needs – neodymium magnets can be manufactured in many forms and dimensions, which amplifies their functionality across industries,
• Key role in advanced technical fields – they are used in hard drives, electric motors, medical equipment or even high-tech tools,
• Relatively small size with high magnetic force – neodymium magnets offer intense magnetic field in tiny dimensions, which makes them useful in small systems

Disadvantages of magnetic elements:

• They may fracture when subjected to a powerful impact. If the magnets are exposed to physical collisions, it is advisable to use in a metal holder. The steel housing, in the form of a holder, protects the magnet from cracks and reinforces its overall durability,
• High temperatures may significantly reduce the strength of neodymium magnets. Typically, above 80°C, they experience permanent loss in performance (depending on height). 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 coated materials,
• The use of a protective casing or external holder is recommended, since machining fine details in neodymium magnets is not feasible,
• Potential hazard due to small fragments may arise, in case of ingestion, which is significant in the protection of children. Furthermore, tiny components from these assemblies may interfere with diagnostics when ingested,
• High unit cost – neodymium magnets are more expensive than other types of magnets (e.g., ferrite), which increases the cost of large-scale applications

Maximum magnetic pulling force – what it depends on?

The given pulling force of the magnet represents the maximum force, measured in the best circumstances, that is:

• with the use of low-carbon steel plate serving as a magnetic yoke
• with a thickness of minimum 10 mm
• with a polished side
• with no separation
• with vertical force applied
• in normal thermal conditions

Determinants of lifting force in real conditions

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, 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 testing was performed on a smooth plate of suitable thickness, under a perpendicular pulling force, in contrast under parallel forces 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.