BM 550x180x70 [4x M8] - magnetic beam

Advantages as well as disadvantages of NdFeB magnets.

Besides their tremendous strength, neodymium magnets offer the following advantages:

• They retain full power for around 10 years – the loss is just ~1% (in theory),
• Magnets effectively resist against demagnetization caused by external fields,
• In other words, due to the glossy layer of silver, the element gains visual value,
• Magnetic induction on the top side of the magnet is impressive,
• Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their shape) at temperatures up to 230°C and above...
• Due to the possibility of precise molding and adaptation to custom requirements, magnetic components can be manufactured in a variety of forms and dimensions, which expands the range of possible applications,
• Wide application in high-tech industry – they are used in mass storage devices, electric drive systems, diagnostic systems, also multitasking production systems.
• Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in tiny dimensions, which allows their use in compact constructions

Characteristics of disadvantages of neodymium magnets: tips and applications.

• They are prone to damage upon heavy impacts. To avoid cracks, it is worth protecting magnets in special housings. Such protection not only protects the magnet but also improves its resistance to damage
• When exposed to high temperature, neodymium magnets experience a drop in force. Often, when the temperature exceeds 80°C, their power decreases (depending on the size and shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding 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 resistant to moisture, when using outdoors
• We suggest casing - magnetic mechanism, due to difficulties in creating nuts inside the magnet and complex shapes.
• Health risk to health – tiny shards of magnets can be dangerous, in case of ingestion, which gains importance in the context of child health protection. It is also worth noting that small components of these magnets are able to be problematic in diagnostics medical after entering the body.
• With budget limitations the cost of neodymium magnets is economically unviable,

Highest magnetic holding force – what affects it?

The load parameter shown represents the maximum value, obtained under laboratory conditions, meaning:

• with the use of a yoke made of low-carbon steel, guaranteeing full magnetic saturation
• whose transverse dimension equals approx. 10 mm
• with a surface free of scratches
• under conditions of no distance (surface-to-surface)
• for force applied at a right angle (in the magnet axis)
• in neutral thermal conditions

Magnet lifting force in use – key factors

In real-world applications, the actual holding force results from several key aspects, listed from the most important:

• Gap between surfaces – even a fraction of a millimeter of separation (caused e.g. by veneer or dirt) drastically reduces the pulling force, often by half at just 0.5 mm.
• Force direction – remember that the magnet holds strongest perpendicularly. Under sliding down, the capacity drops drastically, often to levels of 20-30% of the nominal value.
• Wall thickness – thin material does not allow full use of the magnet. Magnetic flux penetrates through instead of converting into lifting capacity.
• Material composition – different alloys reacts the same. High carbon content weaken the interaction with the magnet.
• Smoothness – ideal contact is obtained only on polished steel. Any scratches and bumps reduce the real contact area, reducing force.
• Thermal conditions – NdFeB sinters have a negative temperature coefficient. At higher temperatures they lose power, and in frost they can be stronger (up to a certain limit).

* Lifting capacity was measured with the use of a steel plate with a smooth surface of optimal thickness (min. 20 mm), under vertically applied force, in contrast under attempts to slide the magnet the load capacity is reduced by as much as 75%. Additionally, even a slight gap {between} the magnet and the plate reduces the load capacity.