ZK XLINK 1026 elementów - construction toy

Strengths and weaknesses of NdFeB magnets.

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

• They virtually do not lose power, because even after 10 years the performance loss is only ~1% (in laboratory conditions),
• They feature excellent resistance to magnetic field loss as a result of external magnetic sources,
• Thanks to the shimmering finish, the plating of nickel, gold, or silver gives an modern appearance,
• They are known for high magnetic induction at the operating surface, making them more effective,
• Neodymium magnets are characterized by extremely high magnetic induction on the magnet surface and can work (depending on the shape) even at a temperature of 230°C or more...
• Possibility of detailed shaping and modifying to concrete needs,
• Fundamental importance in innovative solutions – they serve a role in magnetic memories, electric motors, medical devices, as well as multitasking production systems.
• Thanks to their power density, small magnets offer high operating force, in miniature format,

Disadvantages of NdFeB magnets:

• They are prone to damage upon too strong impacts. To avoid cracks, it is worth protecting magnets in a protective case. Such protection not only protects the magnet but also improves its resistance to damage
• Neodymium magnets decrease their force 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 durability even at temperatures up to 230°C
• When exposed to humidity, magnets usually rust. To use them in conditions outside, it is recommended to use protective magnets, such as magnets in rubber or plastics, which prevent oxidation as well as corrosion.
• We suggest a housing - magnetic holder, due to difficulties in creating threads inside the magnet and complicated forms.
• Health risk resulting from small fragments of magnets can be dangerous, in case of ingestion, which becomes key in the context of child safety. Furthermore, small components of these products can complicate diagnosis medical after entering the body.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

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

The lifting capacity listed is a result of laboratory testing conducted under the following configuration:

• on a base made of structural steel, effectively closing the magnetic flux
• with a cross-section minimum 10 mm
• with a surface cleaned and smooth
• without any clearance between the magnet and steel
• during pulling in a direction vertical to the mounting surface
• in stable room temperature

Lifting capacity in real conditions – factors

Holding efficiency is affected by working environment parameters, including (from priority):

• Clearance – existence of foreign body (rust, dirt, air) interrupts the magnetic circuit, which reduces capacity rapidly (even by 50% at 0.5 mm).
• Force direction – declared lifting capacity refers to pulling vertically. When attempting to slide, the magnet holds much less (typically approx. 20-30% of nominal force).
• Base massiveness – too thin plate does not accept the full field, causing part of the power to be escaped to the other side.
• Metal type – different alloys reacts the same. Alloy additives weaken the attraction effect.
• Smoothness – full contact is obtained only on polished steel. Any scratches and bumps reduce the real contact area, weakening the magnet.
• Thermal factor – high temperature weakens magnetic field. Too high temperature can permanently damage the magnet.

* Holding force was checked on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, whereas under shearing force the holding force is lower. Moreover, even a minimal clearance {between} the magnet and the plate decreases the lifting capacity.