RM R3 - 13000 Gs / N52 - magnetic distributor

Advantages and disadvantages of neodymium magnets NdFeB.

In addition to their remarkable pulling force, neodymium magnets offer the following advantages:

• Their magnetic field remains stable, and after around ten years, it drops only by ~1% (according to research),
• They show superior resistance to demagnetization from external magnetic fields,
• By applying a reflective layer of gold, the element gains a clean look,
• They exhibit extremely high levels of magnetic induction near the outer area of the magnet,
• These magnets tolerate high temperatures, often exceeding 230°C, when properly designed (in relation to profile),
• The ability for accurate shaping or adjustment to individual needs – neodymium magnets can be manufactured in many forms and dimensions, which enhances their versatility in applications,
• Wide application in advanced technical fields – they are used in HDDs, electric motors, diagnostic apparatus and other advanced devices,
• Compactness – despite their small size, they provide high effectiveness, making them ideal for precision applications

Disadvantages of rare earth magnets:

• They can break when subjected to a powerful impact. If the magnets are exposed to shocks, it is suggested to place them in a metal holder. The steel housing, in the form of a holder, protects the magnet from fracture , and at the same time enhances its overall strength,
• Magnets lose magnetic efficiency when exposed to temperatures exceeding 80°C. In most cases, this leads to irreversible performance loss (influenced by the magnet’s dimensions). To address this, we provide [AH] models with superior thermal resistance, able to operate even at 230°C or more,
• Magnets exposed to humidity can corrode. Therefore, for outdoor applications, it's best to use waterproof types made of rubber,
• Limited ability to create threads in the magnet – the use of a magnetic holder is recommended,
• Health risk linked to microscopic shards may arise, if ingested accidentally, which is significant in the health of young users. Moreover, small elements from these assemblies have the potential to complicate medical imaging once in the system,
• Higher purchase price is an important factor to consider compared to ceramic magnets, especially in budget-sensitive applications

Maximum lifting capacity of the magnet – what contributes to it?

The given strength of the magnet corresponds to the optimal strength, assessed in the best circumstances, namely:

• with the use of low-carbon steel plate serving as a magnetic yoke
• having a thickness of no less than 10 millimeters
• with a polished side
• with no separation
• under perpendicular detachment force
• at room temperature

Practical lifting capacity: influencing factors

In practice, the holding capacity of a magnet is conditioned by these factors, in descending order of importance:

• 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.

* Holding force was checked on the plate surface of 20 mm thickness, when the force acted perpendicularly, in contrast under attempts to slide the magnet the lifting capacity is smaller. Additionally, even a small distance {between} the magnet and the plate reduces the load capacity.