UMP 75x25 [M10x3] GW F200 PLATINIUM / N52 - search holder

Strengths and weaknesses of NdFeB magnets.

Besides their stability, neodymium magnets are valued for these benefits:

• Their power is durable, and after around ten years it decreases only by ~1% (theoretically),
• They show high resistance to demagnetization induced by presence of other magnetic fields,
• The use of an shiny layer of noble metals (nickel, gold, silver) causes the element to be more visually attractive,
• The surface of neodymium magnets generates a unique magnetic field – this is a key feature,
• Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their shape) at temperatures up to 230°C and above...
• Due to the option of precise shaping and customization to unique requirements, magnetic components can be manufactured in a broad palette of shapes and sizes, which makes them more universal,
• Huge importance in innovative solutions – they serve a role in mass storage devices, brushless drives, precision medical tools, as well as industrial machines.
• Thanks to concentrated force, small magnets offer high operating force, in miniature format,

Disadvantages of NdFeB magnets:

• They are fragile upon heavy impacts. To avoid cracks, it is worth protecting magnets in special housings. Such protection not only shields the magnet but also improves its resistance to damage
• NdFeB magnets lose power when exposed to high temperatures. After reaching 80°C, many of them experience permanent weakening of power (a factor is the shape as well as dimensions of the magnet). We offer magnets specially adapted to work at temperatures up to 230°C marked [AH], which are extremely resistant to heat
• They oxidize in a humid environment. For use outdoors we advise using waterproof magnets e.g. in rubber, plastic
• Limited ability of producing nuts in the magnet and complicated forms - recommended is casing - magnetic holder.
• Possible danger to health – tiny shards of magnets are risky, in case of ingestion, which is particularly important in the context of child safety. Additionally, small elements of these products can be problematic in diagnostics medical in case of swallowing.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

Breakaway strength of the magnet in ideal conditions – what contributes to it?

The specified lifting capacity represents the limit force, measured under laboratory conditions, specifically:

• on a block made of mild steel, effectively closing the magnetic flux
• possessing a massiveness of min. 10 mm to avoid saturation
• with a plane free of scratches
• without the slightest clearance between the magnet and steel
• for force acting at a right angle (in the magnet axis)
• in temp. approx. 20°C

Practical aspects of lifting capacity – factors

In real-world applications, the actual lifting capacity results from several key aspects, ranked from crucial:

• Gap between magnet and steel – even a fraction of a millimeter of distance (caused e.g. by veneer or dirt) diminishes the magnet efficiency, often by half at just 0.5 mm.
• Force direction – catalog parameter refers to pulling vertically. When slipping, the magnet exhibits much less (often approx. 20-30% of maximum force).
• Metal thickness – the thinner the sheet, the weaker the hold. Part of the magnetic field passes through the material instead of generating force.
• Steel type – mild steel attracts best. Alloy steels reduce magnetic permeability and holding force.
• Plate texture – ground elements guarantee perfect abutment, which increases field saturation. Rough surfaces weaken the grip.
• Thermal environment – heating the magnet results in weakening of induction. It is worth remembering the thermal limit for a given model.

* Lifting capacity testing was carried out on a smooth plate of optimal thickness, under a perpendicular pulling force, whereas under parallel forces the lifting capacity is smaller. Moreover, even a minimal clearance {between} the magnet and the plate reduces the lifting capacity.