MW 14x10 / N38 - cylindrical magnet

Pros as well as cons of NdFeB magnets.

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

• They virtually do not lose strength, because even after ten years the decline in efficiency is only ~1% (in laboratory conditions),
• Magnets effectively protect themselves against loss of magnetization caused by foreign field sources,
• By covering with a reflective layer of gold, the element gains an proper look,
• Magnetic induction on the top side of the magnet is impressive,
• Through (appropriate) combination of ingredients, they can achieve high thermal resistance, enabling action at temperatures approaching 230°C and above...
• Thanks to freedom in forming and the capacity to modify to specific needs,
• Fundamental importance in advanced technology sectors – they serve a role in computer drives, electromotive mechanisms, medical equipment, also industrial machines.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in compact dimensions, which allows their use in small systems

Problematic aspects of neodymium magnets: application proposals

• They are prone to damage upon heavy impacts. To avoid cracks, it is worth securing magnets in special housings. Such protection not only protects the magnet but also improves its resistance to damage
• Neodymium magnets decrease their strength under the influence of heating. As soon as 80°C is exceeded, many of them start losing their power. Therefore, we recommend our special magnets marked [AH], which maintain stability even at temperatures up to 230°C
• They oxidize in a humid environment - during use outdoors we recommend using waterproof magnets e.g. in rubber, plastic
• We suggest casing - magnetic mechanism, due to difficulties in creating threads inside the magnet and complicated shapes.
• Potential hazard to health – tiny shards of magnets are risky, when accidentally swallowed, which is particularly important in the context of child safety. Furthermore, small elements of these products are able to be problematic in diagnostics medical in case of swallowing.
• Due to expensive raw materials, their price is higher than average,

Best holding force of the magnet in ideal parameters – what affects it?

The load parameter shown concerns the maximum value, obtained under ideal test conditions, meaning:

• with the use of a yoke made of special test steel, guaranteeing maximum field concentration
• possessing a massiveness of min. 10 mm to avoid saturation
• with a plane cleaned and smooth
• under conditions of gap-free contact (surface-to-surface)
• during detachment in a direction perpendicular to the mounting surface
• at standard ambient temperature

Practical lifting capacity: influencing factors

Real force is affected by specific conditions, including (from most important):

• Space between surfaces – even a fraction of a millimeter of distance (caused e.g. by varnish or dirt) drastically reduces the pulling force, often by half at just 0.5 mm.
• Load vector – highest force is available only during pulling at a 90° angle. The resistance to sliding of the magnet along the surface is standardly many times smaller (approx. 1/5 of the lifting capacity).
• Metal thickness – the thinner the sheet, the weaker the hold. Magnetic flux penetrates through instead of converting into lifting capacity.
• Material composition – different alloys attracts identically. High carbon content worsen the interaction with the magnet.
• Plate texture – smooth surfaces ensure maximum contact, which improves force. Rough surfaces reduce efficiency.
• Thermal environment – temperature increase results in weakening of force. Check the thermal limit for a given model.

* Lifting capacity testing was conducted on plates with a smooth surface of optimal thickness, under a perpendicular pulling force, in contrast under parallel forces the lifting capacity is smaller. Moreover, even a minimal clearance {between} the magnet’s surface and the plate decreases the load capacity.