UMP 94x40 [3xM10] GW F550 Silver Black Lina / N52 - search holder

Advantages and disadvantages of neodymium magnets NdFeB.

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

• They retain their attractive force for almost 10 years – the loss is just ~1% (according to analyses),
• They are very resistant to demagnetization caused by external field interference,
• In other words, due to the metallic nickel coating, the magnet obtains an stylish appearance,
• They have exceptional magnetic induction on the surface of the magnet,
• Neodymium magnets are known for exceptionally strong magnetic induction and the ability to work at temperatures up to 230°C or higher (depending on the shape),
• With the option for tailored forming and targeted design, these magnets can be produced in various shapes and sizes, greatly improving engineering flexibility,
• Wide application in modern technologies – they are utilized in data storage devices, rotating machines, diagnostic apparatus and technologically developed systems,
• Thanks to their efficiency per volume, small magnets offer high magnetic performance, with minimal size,

Disadvantages of magnetic elements:

• They can break when subjected to a sudden impact. If the magnets are exposed to shocks, it is suggested to place them in a protective case. The steel housing, in the form of a holder, protects the magnet from damage while also strengthens its overall strength,
• Magnets lose magnetic efficiency when exposed to temperatures exceeding 80°C. In most cases, this leads to irreversible magnetic decay (influenced by the magnet’s structure). To address this, we provide [AH] models with superior thermal resistance, able to operate even at 230°C or more,
• They rust in a humid environment. If exposed to rain, we recommend using moisture-resistant magnets, such as those 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, in case of ingestion, which is important in the family environments. Moreover, tiny components from these devices may complicate medical imaging after being swallowed,
• In cases of tight budgets, neodymium magnet cost may be a barrier,

Maximum lifting capacity of the magnet – what affects it?

The given strength of the magnet represents the optimal strength, determined under optimal conditions, namely:

• with mild steel, serving as a magnetic flux conductor
• of a thickness of at least 10 mm
• with a smooth surface
• in conditions of no clearance
• in a perpendicular direction of force
• at room temperature

Lifting capacity in real conditions – factors

Practical lifting force is dependent on factors, by priority:

• Air gap between the magnet and the plate, as 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 with the use of a steel plate with a smooth surface of optimal thickness (min. 20 mm), under vertically applied force, whereas under shearing force the lifting capacity is smaller. Moreover, even a minimal clearance {between} the magnet and the plate decreases the load capacity.