MPL 50x20x5 / N38 - lamellar magnet

Pros and cons of neodymium magnets.

Apart from their notable holding force, neodymium magnets have these key benefits:

• They have constant strength, and over nearly 10 years their performance decreases symbolically – ~1% (according to theory),
• They do not lose their magnetic properties even under external field action,
• In other words, due to the shiny finish of gold, the element is aesthetically pleasing,
• Neodymium magnets deliver maximum magnetic induction on a their surface, which ensures high operational effectiveness,
• Due to their durability and thermal resistance, neodymium magnets are capable of operate (depending on the shape) even at high temperatures reaching 230°C or more...
• Thanks to versatility in forming and the ability to customize to specific needs,
• Key role in high-tech industry – they are utilized in mass storage devices, electric drive systems, advanced medical instruments, and other advanced devices.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in small dimensions, which makes them useful in miniature devices

Disadvantages of neodymium magnets:

• Susceptibility to cracking is one of their disadvantages. Upon strong impact they can fracture. We advise keeping them in a strong case, which not only secures them against impacts but also increases their durability
• Neodymium magnets decrease their power 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 durability even at temperatures up to 230°C
• Magnets exposed to a humid environment can rust. Therefore during using outdoors, we suggest using water-impermeable magnets made of rubber, plastic or other material protecting against moisture
• Due to limitations in producing threads and complex shapes in magnets, we recommend using a housing - magnetic holder.
• Health risk resulting from small fragments of magnets are risky, in case of ingestion, which becomes key in the aspect of protecting the youngest. Furthermore, small elements of these devices can be problematic in diagnostics medical when they are in the body.
• With large orders the cost of neodymium magnets is a challenge,

Highest magnetic holding force – what contributes to it?

Holding force of 12.49 kg is a theoretical maximum value executed under standard conditions:

• with the application of a sheet made of special test steel, guaranteeing full magnetic saturation
• possessing a thickness of at least 10 mm to ensure full flux closure
• with an ideally smooth contact surface
• without the slightest air gap between the magnet and steel
• for force applied at a right angle (in the magnet axis)
• in neutral thermal conditions

Lifting capacity in real conditions – factors

It is worth knowing that the magnet holding will differ depending on the following factors, starting with the most relevant:

• Gap (between the magnet and the metal), as even a very small clearance (e.g. 0.5 mm) can cause a decrease in lifting capacity by up to 50% (this also applies to paint, corrosion or debris).
• Direction of force – highest force is reached only during perpendicular pulling. The force required to slide of the magnet along the surface is typically several times smaller (approx. 1/5 of the lifting capacity).
• Base massiveness – insufficiently thick sheet does not close the flux, causing part of the flux to be escaped into the air.
• Material type – ideal substrate is pure iron steel. Hardened steels may have worse magnetic properties.
• Surface finish – full contact is possible only on smooth steel. Rough texture create air cushions, reducing force.
• Temperature – temperature increase results in weakening of induction. It is worth remembering the maximum operating temperature for a given model.

* Holding force was checked on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, in contrast under shearing force the holding force is lower. Additionally, even a slight gap {between} the magnet’s surface and the plate decreases the load capacity.