MW 55x25 / N38 - cylindrical magnet

Strengths and weaknesses of NdFeB magnets.

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

• Their power is durable, and after around ten years it decreases only by ~1% (theoretically),
• Neodymium magnets are characterized by highly resistant to loss of magnetic properties caused by external field sources,
• By covering with a decorative layer of silver, the element acquires an modern look,
• The surface of neodymium magnets generates a unique magnetic field – this is a key feature,
• 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 designing and the ability to adapt to specific needs,
• Key role in future technologies – they serve a role in mass storage devices, drive modules, medical devices, as well as modern systems.
• Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in tiny dimensions, which enables their usage in small systems

Characteristics of disadvantages of neodymium magnets: weaknesses and usage proposals

• At very strong impacts they can break, therefore we recommend placing them in steel cases. A metal housing provides additional protection against damage and increases the magnet's durability.
• We warn that neodymium magnets can lose their strength at high temperatures. To prevent this, we suggest our specialized [AH] magnets, which work effectively even at 230°C.
• Due to the susceptibility of magnets to corrosion in a humid environment, we suggest using waterproof magnets made of rubber, plastic or other material stable to moisture, in case of application outdoors
• Due to limitations in creating nuts and complicated shapes in magnets, we propose using a housing - magnetic mount.
• Possible danger to health – tiny shards of magnets are risky, when accidentally swallowed, which gains importance in the context of child safety. Furthermore, tiny parts of these products are able to be problematic in diagnostics medical after entering the body.
• Due to complex production process, their price is relatively high,

Breakaway strength of the magnet in ideal conditions – what affects it?

The lifting capacity listed is a theoretical maximum value performed under the following configuration:

• with the application of a sheet made of low-carbon steel, guaranteeing maximum field concentration
• with a thickness no less than 10 mm
• characterized by even structure
• without any clearance between the magnet and steel
• for force applied at a right angle (pull-off, not shear)
• at ambient temperature approx. 20 degrees Celsius

Magnet lifting force in use – key factors

In real-world applications, the real power results from a number of factors, presented from crucial:

• Space between surfaces – every millimeter of distance (caused e.g. by varnish or dirt) significantly weakens the magnet efficiency, often by half at just 0.5 mm.
• Force direction – declared lifting capacity refers to detachment vertically. When applying parallel force, the magnet exhibits much less (typically approx. 20-30% of maximum force).
• Substrate thickness – for full efficiency, the steel must be adequately massive. Thin sheet restricts the attraction force (the magnet "punches through" it).
• Plate material – low-carbon steel gives the best results. Alloy admixtures decrease magnetic properties and holding force.
• Surface quality – the smoother and more polished the surface, the larger the contact zone and higher the lifting capacity. Roughness creates an air distance.
• Temperature – heating the magnet results in weakening of induction. It is worth remembering the thermal limit for a given model.

* Lifting capacity testing was conducted on plates with a smooth surface of optimal thickness, under perpendicular forces, whereas under attempts to slide the magnet the holding force is lower. Additionally, even a minimal clearance {between} the magnet’s surface and the plate reduces the load capacity.