MW 8x15 / N38 - cylindrical magnet

Pros as well as cons of neodymium magnets.

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

• They retain magnetic properties for almost 10 years – the loss is just ~1% (based on simulations),
• Magnets effectively resist against loss of magnetization caused by external fields,
• The use of an metallic layer of noble metals (nickel, gold, silver) causes the element to be more visually attractive,
• Neodymium magnets generate maximum magnetic induction on a small surface, which ensures high operational effectiveness,
• Due to their durability and thermal resistance, neodymium magnets can operate (depending on the shape) even at high temperatures reaching 230°C or more...
• Possibility of custom machining and adapting to defined conditions,
• Key role in high-tech industry – they are commonly used in data components, electromotive mechanisms, medical devices, as well as technologically advanced constructions.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in small dimensions, which allows their use in small systems

Disadvantages of NdFeB magnets:

• At very strong impacts they can crack, 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 reduce their power at high temperatures. To prevent this, we suggest our specialized [AH] magnets, which work effectively even at 230°C.
• Magnets exposed to a humid environment can rust. Therefore when using outdoors, we suggest using water-impermeable magnets made of rubber, plastic or other material resistant to moisture
• We recommend casing - magnetic mount, due to difficulties in producing nuts inside the magnet and complex shapes.
• Health risk to health – tiny shards of magnets are risky, if swallowed, which becomes key in the context of child safety. Additionally, tiny parts of these devices are able to be problematic in diagnostics medical in case of swallowing.
• High unit price – neodymium magnets are more expensive than other types of magnets (e.g. ferrite), which can limit application in large quantities

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

The specified lifting capacity refers to the limit force, recorded under laboratory conditions, specifically:

• on a base made of structural steel, optimally conducting the magnetic field
• possessing a massiveness of min. 10 mm to avoid saturation
• characterized by lack of roughness
• with direct contact (no impurities)
• under axial force vector (90-degree angle)
• at temperature approx. 20 degrees Celsius

Lifting capacity in practice – influencing factors

Please note that the application force may be lower depending on elements below, starting with the most relevant:

• Distance (between the magnet and the plate), because even a microscopic distance (e.g. 0.5 mm) can cause a drastic drop in force by up to 50% (this also applies to paint, corrosion or debris).
• Pull-off angle – remember that the magnet has greatest strength perpendicularly. Under shear forces, the capacity drops drastically, often to levels of 20-30% of the nominal value.
• Steel thickness – insufficiently thick plate does not accept the full field, causing part of the power to be escaped into the air.
• Steel type – mild steel gives the best results. Alloy admixtures reduce magnetic properties and lifting capacity.
• Smoothness – full contact is obtained only on smooth steel. Any scratches and bumps create air cushions, weakening the magnet.
• Temperature – temperature increase causes a temporary drop of induction. Check the maximum operating temperature for a given model.

* Lifting capacity testing was performed on plates with a smooth surface of suitable thickness, under perpendicular forces, however under shearing force the lifting capacity is smaller. In addition, even a small distance {between} the magnet and the plate lowers the holding force.