MPL 40x18x10 SH / N38 - lamellar magnet

Strengths and weaknesses of NdFeB magnets.

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

• They retain magnetic properties for around 10 years – the drop is just ~1% (according to analyses),
• Neodymium magnets remain extremely resistant to magnetic field loss caused by external magnetic fields,
• Thanks to the metallic finish, the layer of nickel, gold, or silver-plated gives an aesthetic appearance,
• Magnetic induction on the working part of the magnet is extremely intense,
• Thanks to resistance to high temperature, they are able to function (depending on the form) even at temperatures up to 230°C and higher...
• Thanks to modularity in constructing and the capacity to modify to specific needs,
• Versatile presence in innovative solutions – they find application in hard drives, motor assemblies, medical equipment, also technologically advanced constructions.
• Compactness – despite small sizes they provide effective action, making them ideal for precision applications

Disadvantages of neodymium magnets:

• Susceptibility to cracking is one of their disadvantages. Upon strong impact they can break. We recommend keeping them in a strong case, which not only protects them against impacts but also raises their durability
• Neodymium magnets lose force when exposed to high temperatures. After reaching 80°C, many of them experience permanent weakening 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 very resistant to heat
• Due to the susceptibility of magnets to corrosion in a humid environment, we recommend using waterproof magnets made of rubber, plastic or other material stable to moisture, when using outdoors
• Due to limitations in realizing threads and complex forms in magnets, we propose using a housing - magnetic mount.
• Potential hazard resulting from small fragments of magnets can be dangerous, in case of ingestion, which is particularly important in the aspect of protecting the youngest. Additionally, small components of these products are able to be problematic in diagnostics medical when they are in the body.
• Due to expensive raw materials, their price is higher than average,

Detachment force of the magnet in optimal conditions – what contributes to it?

The force parameter is a theoretical maximum value executed under standard conditions:

• on a plate made of mild steel, perfectly concentrating the magnetic field
• whose transverse dimension equals approx. 10 mm
• characterized by even structure
• under conditions of no distance (metal-to-metal)
• during pulling in a direction vertical to the mounting surface
• at room temperature

Key elements affecting lifting force

Please note that the application force may be lower depending on the following factors, in order of importance:

• Clearance – existence of foreign body (paint, tape, air) acts as an insulator, which reduces capacity steeply (even by 50% at 0.5 mm).
• Load vector – highest force is obtained only during perpendicular pulling. The shear force of the magnet along the plate is standardly several times lower (approx. 1/5 of the lifting capacity).
• Plate thickness – insufficiently thick plate does not accept the full field, causing part of the flux to be wasted into the air.
• Steel type – low-carbon steel gives the best results. Higher carbon content reduce magnetic permeability and holding force.
• Surface quality – the more even the surface, the better the adhesion and higher the lifting capacity. Roughness creates an air distance.
• Thermal factor – high temperature reduces magnetic field. Exceeding the limit temperature can permanently damage the magnet.

* Lifting capacity was determined with the use of a steel plate with a smooth surface of suitable thickness (min. 20 mm), under perpendicular detachment force, however under parallel forces the load capacity is reduced by as much as fivefold. Moreover, even a slight gap {between} the magnet and the plate lowers the lifting capacity.