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

Advantages as well as disadvantages of neodymium magnets.

Besides their remarkable field intensity, neodymium magnets offer the following advantages:

• They retain magnetic properties for nearly ten years – the loss is just ~1% (in theory),
• Magnets perfectly defend themselves against demagnetization caused by external fields,
• Thanks to the shimmering finish, the surface of nickel, gold-plated, or silver gives an modern appearance,
• Magnetic induction on the working part of the magnet turns out to be very high,
• Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their form) at temperatures up to 230°C and above...
• Possibility of custom forming as well as adapting to defined applications,
• Key role in high-tech industry – they are utilized in mass storage devices, electromotive mechanisms, precision medical tools, as well as multitasking production systems.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in tiny dimensions, which makes them useful in miniature devices

Drawbacks and weaknesses of neodymium magnets: application proposals

• They are fragile upon heavy impacts. To avoid cracks, it is worth protecting magnets in a protective case. Such protection not only shields the magnet but also increases its resistance to damage
• Neodymium magnets lose their strength under the influence of heating. As soon as 80°C is exceeded, many of them start losing their force. Therefore, we recommend our special magnets marked [AH], which maintain stability even at temperatures up to 230°C
• Due to the susceptibility of magnets to corrosion in a humid environment, we advise using waterproof magnets made of rubber, plastic or other material resistant to moisture, in case of application outdoors
• Due to limitations in realizing nuts and complicated forms in magnets, we recommend using cover - magnetic mount.
• Possible danger resulting from small fragments of magnets are risky, in case of ingestion, which is particularly important in the aspect of protecting the youngest. Additionally, small elements of these magnets can complicate diagnosis medical after entering the body.
• High unit price – neodymium magnets have a higher price than other types of magnets (e.g. ferrite), which hinders application in large quantities

Maximum lifting capacity of the magnet – what it depends on?

The force parameter is a result of laboratory testing executed under specific, ideal conditions:

• with the use of a yoke made of special test steel, ensuring full magnetic saturation
• possessing a massiveness of min. 10 mm to ensure full flux closure
• characterized by lack of roughness
• under conditions of ideal adhesion (metal-to-metal)
• for force applied at a right angle (in the magnet axis)
• at temperature room level

Practical lifting capacity: influencing factors

Bear in mind that the application force may be lower subject to elements below, starting with the most relevant:

• Gap (betwixt the magnet and the metal), since even a tiny clearance (e.g. 0.5 mm) leads to a reduction in force by up to 50% (this also applies to varnish, rust or dirt).
• Pull-off angle – remember that the magnet has greatest strength perpendicularly. Under sliding down, the capacity drops significantly, often to levels of 20-30% of the maximum value.
• Substrate thickness – for full efficiency, the steel must be sufficiently thick. Thin sheet limits the lifting capacity (the magnet "punches through" it).
• Metal type – not every steel reacts the same. Alloy additives worsen the interaction with the magnet.
• Surface condition – smooth surfaces guarantee perfect abutment, which improves force. Rough surfaces weaken the grip.
• Thermal environment – temperature increase results in weakening of induction. It is worth remembering the thermal limit for a given model.

* Lifting capacity testing was carried out on plates with a smooth surface of suitable thickness, under perpendicular forces, in contrast under parallel forces the holding force is lower. Moreover, even a small distance {between} the magnet’s surface and the plate reduces the lifting capacity.