BM 320x180x70 [4x M8] - magnetic beam

Advantages and disadvantages of NdFeB magnets.

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

• Their magnetic field remains stable, and after approximately 10 years it decreases only by ~1% (theoretically),
• They do not lose their magnetic properties even under close interference source,
• A magnet with a shiny nickel surface has an effective appearance,
• Magnets exhibit exceptionally strong magnetic induction on the surface,
• Due to their durability and thermal resistance, neodymium magnets can operate (depending on the form) even at high temperatures reaching 230°C or more...
• Thanks to the potential of precise molding and adaptation to custom projects, NdFeB magnets can be manufactured in a wide range of forms and dimensions, which makes them more universal,
• Significant place in modern technologies – they are used in mass storage devices, brushless drives, advanced medical instruments, as well as complex engineering applications.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

Disadvantages of neodymium magnets:

• At strong impacts they can crack, therefore we advise placing them in special holders. A metal housing provides additional protection against damage and increases the magnet's durability.
• Neodymium magnets decrease their strength 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
• Magnets exposed to a humid environment can rust. Therefore during using outdoors, we suggest using waterproof magnets made of rubber, plastic or other material resistant to moisture
• Due to limitations in realizing nuts and complex forms in magnets, we recommend using a housing - magnetic holder.
• Health risk to health – tiny shards of magnets can be dangerous, when accidentally swallowed, which gains importance in the aspect of protecting the youngest. Furthermore, tiny parts of these devices are able to disrupt the diagnostic process medical when they are in the body.
• With budget limitations the cost of neodymium magnets is a challenge,

Magnetic strength at its maximum – what contributes to it?

The declared magnet strength refers to the maximum value, measured under laboratory conditions, namely:

• with the application of a yoke made of special test steel, ensuring maximum field concentration
• with a thickness of at least 10 mm
• with an polished touching surface
• under conditions of ideal adhesion (metal-to-metal)
• for force applied at a right angle (in the magnet axis)
• in stable room temperature

Lifting capacity in practice – influencing factors

It is worth knowing that the application force will differ subject to the following factors, starting with the most relevant:

• Distance (between the magnet and the metal), as even a tiny clearance (e.g. 0.5 mm) results in a drastic drop in force by up to 50% (this also applies to varnish, rust or debris).
• Pull-off angle – note that the magnet holds strongest perpendicularly. Under sliding down, the holding force drops drastically, often to levels of 20-30% of the nominal value.
• Substrate thickness – to utilize 100% power, the steel must be sufficiently thick. Thin sheet limits the attraction force (the magnet "punches through" it).
• Material type – ideal substrate is high-permeability steel. Cast iron may have worse magnetic properties.
• Surface condition – smooth surfaces ensure maximum contact, which increases field saturation. Uneven metal reduce efficiency.
• Temperature influence – hot environment reduces pulling force. Exceeding the limit temperature can permanently demagnetize the magnet.

* Lifting capacity testing was carried out on plates with a smooth surface of optimal thickness, under perpendicular forces, whereas under attempts to slide the magnet the lifting capacity is smaller. In addition, even a slight gap {between} the magnet and the plate reduces the lifting capacity.