MPL 40x40x15 / N38 - lamellar magnet

Advantages as well as disadvantages of rare earth magnets.

Besides their magnetic performance, neodymium magnets are valued for these benefits:

• They have unchanged lifting capacity, and over more than 10 years their performance decreases symbolically – ~1% (in testing),
• They are noted for resistance to demagnetization induced by external magnetic fields,
• By covering with a decorative layer of nickel, the element gains an proper look,
• The surface of neodymium magnets generates a intense magnetic field – this is one of their assets,
• Thanks to resistance to high temperature, they are able to function (depending on the shape) even at temperatures up to 230°C and higher...
• Possibility of exact machining and adapting to precise requirements,
• Huge importance in high-tech industry – they find application in magnetic memories, motor assemblies, advanced medical instruments, as well as multitasking production systems.
• Thanks to concentrated force, small magnets offer high operating force, occupying minimum space,

Drawbacks and weaknesses of neodymium magnets: application proposals

• At strong impacts they can break, therefore we advise placing them in special holders. A metal housing provides additional protection against damage and increases the magnet's durability.
• NdFeB magnets demagnetize when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop of power (a factor is the shape and 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
• Due to the susceptibility of magnets to corrosion in a humid environment, we advise using waterproof magnets made of rubber, plastic or other material stable to moisture, in case of application outdoors
• Due to limitations in realizing nuts and complex shapes in magnets, we propose using cover - magnetic mount.
• Possible danger resulting from small fragments of magnets are risky, if swallowed, which becomes key in the context of child health protection. Additionally, tiny parts of these products are able to complicate diagnosis medical when they are in the body.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

Maximum lifting force for a neodymium magnet – what contributes to it?

The specified lifting capacity refers to the maximum value, recorded under optimal environment, namely:

• on a plate made of structural steel, optimally conducting the magnetic flux
• whose thickness equals approx. 10 mm
• with a surface free of scratches
• with zero gap (without impurities)
• under vertical force vector (90-degree angle)
• at ambient temperature room level

Lifting capacity in practice – influencing factors

Bear in mind that the magnet holding may be lower influenced by the following factors, starting with the most relevant:

• Distance – existence of any layer (rust, tape, air) interrupts the magnetic circuit, which lowers power steeply (even by 50% at 0.5 mm).
• Direction of force – highest force is reached only during perpendicular pulling. The resistance to sliding of the magnet along the plate is typically several times lower (approx. 1/5 of the lifting capacity).
• Substrate thickness – to utilize 100% power, the steel must be adequately massive. Thin sheet limits the lifting capacity (the magnet "punches through" it).
• Chemical composition of the base – low-carbon steel attracts best. Alloy admixtures decrease magnetic permeability and holding force.
• Surface structure – the more even the plate, the larger the contact zone and higher the lifting capacity. Unevenness acts like micro-gaps.
• Thermal factor – hot environment reduces magnetic field. Exceeding the limit temperature can permanently damage the magnet.

* Lifting capacity was measured with the use of a smooth steel plate of optimal thickness (min. 20 mm), under perpendicular pulling force, in contrast under attempts to slide the magnet the lifting capacity is smaller. In addition, even a minimal clearance {between} the magnet’s surface and the plate lowers the load capacity.