MP 41x15x10 / N38 - ring magnet

Advantages as well as disadvantages of NdFeB magnets.

Besides their stability, neodymium magnets are valued for these benefits:

• They retain magnetic properties for almost ten years – the drop is just ~1% (based on simulations),
• They retain their magnetic properties even under close interference source,
• By covering with a decorative coating of gold, the element presents an elegant look,
• The surface of neodymium magnets generates a strong magnetic field – this is one of their assets,
• Through (adequate) combination of ingredients, they can achieve high thermal resistance, enabling functioning at temperatures approaching 230°C and above...
• Possibility of detailed creating as well as adjusting to concrete conditions,
• Huge importance in innovative solutions – they find application in hard drives, electric drive systems, medical devices, also multitasking production systems.
• Thanks to efficiency per cm³, small magnets offer high operating force, with minimal size,

Disadvantages of neodymium magnets:

• They are prone to damage upon heavy impacts. To avoid cracks, it is worth protecting magnets using a steel holder. Such protection not only protects the magnet but also increases 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
• Due to the susceptibility of magnets to corrosion in a humid environment, we suggest using waterproof magnets made of rubber, plastic or other material immune to moisture, in case of application outdoors
• Due to limitations in creating nuts and complicated shapes in magnets, we propose using casing - magnetic mechanism.
• Health risk to health – tiny shards of magnets pose a threat, when accidentally swallowed, 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 in case of swallowing.
• With budget limitations the cost of neodymium magnets is economically unviable,

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

Holding force of 11.36 kg is a theoretical maximum value performed under standard conditions:

• with the use of a yoke made of special test steel, ensuring maximum field concentration
• whose thickness reaches at least 10 mm
• with an polished touching surface
• under conditions of gap-free contact (surface-to-surface)
• under vertical force vector (90-degree angle)
• at standard ambient temperature

Lifting capacity in real conditions – factors

Effective lifting capacity is affected by working environment parameters, such as (from most important):

• Distance – the presence of foreign body (paint, dirt, gap) acts as an insulator, which lowers capacity steeply (even by 50% at 0.5 mm).
• Loading method – catalog parameter refers to pulling vertically. When slipping, the magnet exhibits much less (often approx. 20-30% of nominal force).
• Metal thickness – the thinner the sheet, the weaker the hold. Magnetic flux penetrates through instead of converting into lifting capacity.
• Material type – ideal substrate is pure iron steel. Cast iron may generate lower lifting capacity.
• Surface condition – smooth surfaces ensure maximum contact, which increases force. Uneven metal reduce efficiency.
• Temperature influence – hot environment reduces pulling force. Too high temperature can permanently demagnetize the magnet.

* Lifting capacity testing was conducted on a smooth plate of optimal thickness, under perpendicular forces, whereas under parallel forces the holding force is lower. Additionally, even a slight gap {between} the magnet’s surface and the plate lowers the load capacity.