MPL 50x20x5 / N38 - lamellar magnet

Pros and cons of rare earth magnets.

Besides their exceptional pulling force, neodymium magnets offer the following advantages:

• Their strength is maintained, and after around 10 years it decreases only by ~1% (theoretically),
• They do not lose their magnetic properties even under strong external field,
• By covering with a decorative layer of silver, the element presents an aesthetic look,
• Magnetic induction on the surface of the magnet remains exceptional,
• 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 accurate modeling and modifying to complex needs,
• Universal use in advanced technology sectors – they find application in mass storage devices, electric drive systems, precision medical tools, as well as other advanced devices.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

Disadvantages of neodymium magnets:

• To avoid cracks under impact, we suggest using special steel holders. Such a solution protects the magnet and simultaneously improves its durability.
• Neodymium magnets decrease their force 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
• When exposed to humidity, magnets start to rust. To use them in conditions outside, it is recommended to use protective magnets, such as magnets in rubber or plastics, which prevent oxidation as well as corrosion.
• Due to limitations in producing threads and complicated forms in magnets, we recommend using a housing - magnetic mount.
• Health risk related to microscopic parts of magnets can be dangerous, if swallowed, which is particularly important in the context of child safety. It is also worth noting that small elements of these magnets can complicate diagnosis medical in case of swallowing.
• 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?

Information about lifting capacity was determined for ideal contact conditions, taking into account:

• on a block made of mild steel, optimally conducting the magnetic flux
• possessing a massiveness of min. 10 mm to ensure full flux closure
• with a surface free of scratches
• under conditions of gap-free contact (metal-to-metal)
• for force applied at a right angle (pull-off, not shear)
• at room temperature

Lifting capacity in real conditions – factors

During everyday use, the actual lifting capacity results from a number of factors, presented from the most important:

• Distance – existence of any layer (rust, tape, air) acts as an insulator, which lowers capacity steeply (even by 50% at 0.5 mm).
• Force direction – note that the magnet has greatest strength perpendicularly. Under shear forces, the capacity drops drastically, often to levels of 20-30% of the maximum value.
• Base massiveness – too thin plate does not accept the full field, causing part of the power to be wasted into the air.
• Material composition – not every steel attracts identically. High carbon content worsen the attraction effect.
• Surface quality – the more even the surface, the larger the contact zone and stronger the hold. Roughness acts like micro-gaps.
• Temperature influence – high temperature weakens magnetic field. Too high temperature can permanently demagnetize the magnet.

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