RM R8 ULTRA - 13000 Gs / N52 - magnetic distributor

Strengths and weaknesses of NdFeB magnets.

Apart from their consistent power, neodymium magnets have these key benefits:

• They retain full power for almost 10 years – the drop is just ~1% (in theory),
• Magnets perfectly protect themselves against loss of magnetization caused by external fields,
• Thanks to the metallic finish, the coating of Ni-Cu-Ni, gold-plated, or silver-plated gives an aesthetic appearance,
• They are known for high magnetic induction at the operating surface, making them more effective,
• Through (appropriate) combination of ingredients, they can achieve high thermal resistance, enabling functioning at temperatures approaching 230°C and above...
• Possibility of precise modeling and optimizing to concrete needs,
• Versatile presence in high-tech industry – they find application in computer drives, electromotive mechanisms, medical equipment, also multitasking production systems.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in compact dimensions, which enables their usage in compact constructions

Disadvantages of NdFeB magnets:

• To avoid cracks upon strong impacts, we recommend using special steel holders. Such a solution protects the magnet and simultaneously increases its durability.
• Neodymium magnets decrease their force under the influence of heating. As soon as 80°C is exceeded, many of them start losing their force. Therefore, we recommend our special magnets marked [AH], which maintain stability even at temperatures up to 230°C
• Due to the susceptibility of magnets to corrosion in a humid environment, we advise using waterproof magnets made of rubber, plastic or other material resistant to moisture, when using outdoors
• Due to limitations in producing threads and complicated forms in magnets, we propose using casing - magnetic holder.
• Health risk resulting from small fragments of magnets can be dangerous, if swallowed, which gains importance in the context of child safety. Furthermore, small elements of these magnets are able to disrupt the diagnostic process medical in case of swallowing.
• With budget limitations the cost of neodymium magnets is economically unviable,

Maximum magnetic pulling force – what it depends on?

Information about lifting capacity was defined for optimal configuration, including:

• using a base made of mild steel, functioning as a magnetic yoke
• whose transverse dimension equals approx. 10 mm
• with an ground contact surface
• with direct contact (no paint)
• for force acting at a right angle (pull-off, not shear)
• at temperature room level

What influences lifting capacity in practice

Holding efficiency impacted by working environment parameters, such as (from priority):

• Gap between magnet and steel – every millimeter of distance (caused e.g. by varnish or dirt) diminishes the pulling force, often by half at just 0.5 mm.
• Pull-off angle – note that the magnet has greatest strength perpendicularly. Under sliding down, the capacity drops significantly, often to levels of 20-30% of the nominal value.
• Element thickness – to utilize 100% power, the steel must be adequately massive. Paper-thin metal restricts the attraction force (the magnet "punches through" it).
• Metal type – not every steel attracts identically. High carbon content worsen the attraction effect.
• Smoothness – ideal contact is possible only on smooth steel. Any scratches and bumps reduce the real contact area, reducing force.
• Temperature influence – hot environment reduces pulling force. Exceeding the limit temperature can permanently damage the magnet.

* Lifting capacity testing was carried out on a smooth plate of optimal thickness, under a perpendicular pulling force, whereas under parallel forces the load capacity is reduced by as much as 5 times. Additionally, even a minimal clearance {between} the magnet’s surface and the plate reduces the holding force.