BM 750x180x70 [4x M8] - magnetic beam

Pros as well as cons of rare earth magnets.

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

• They do not lose strength, even during nearly ten years – the reduction in strength is only ~1% (according to tests),
• Magnets very well defend themselves against demagnetization caused by foreign field sources,
• A magnet with a smooth nickel surface has an effective appearance,
• Magnetic induction on the top side of the magnet turns out to be very high,
• Thanks to resistance to high temperature, they are capable of working (depending on the form) even at temperatures up to 230°C and higher...
• Thanks to versatility in forming and the capacity to adapt to complex applications,
• Fundamental importance in modern industrial fields – they serve a role in HDD drives, brushless drives, medical equipment, as well as complex engineering applications.
• Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications

Drawbacks and weaknesses of neodymium magnets: application proposals

• They are fragile upon too strong impacts. To avoid cracks, it is worth protecting magnets using a steel holder. Such protection not only shields the magnet but also improves 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 force. Therefore, we recommend our special magnets marked [AH], which maintain durability 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 resistant to moisture, when using outdoors
• Due to limitations in creating nuts and complex forms in magnets, we propose using casing - magnetic holder.
• Potential hazard related to microscopic parts of magnets pose a threat, if swallowed, which becomes key in the context of child safety. Furthermore, small components of these devices can complicate diagnosis medical when they are in the body.
• Due to complex production process, their price is relatively high,

Maximum lifting force for a neodymium magnet – what affects it?

The load parameter shown concerns the peak performance, measured under ideal test conditions, specifically:

• with the application of a sheet made of low-carbon steel, ensuring maximum field concentration
• whose thickness is min. 10 mm
• characterized by even structure
• without any air gap between the magnet and steel
• during detachment in a direction perpendicular to the plane
• at ambient temperature approx. 20 degrees Celsius

Key elements affecting lifting force

Bear in mind that the magnet holding may be lower influenced by elements below, in order of importance:

• Distance (betwixt the magnet and the plate), since even a microscopic distance (e.g. 0.5 mm) results in a drastic drop in lifting capacity by up to 50% (this also applies to paint, corrosion or debris).
• Load vector – maximum parameter is obtained only during pulling at a 90° angle. The force required to slide of the magnet along the plate is standardly many times lower (approx. 1/5 of the lifting capacity).
• Plate thickness – insufficiently thick sheet does not accept the full field, causing part of the power to be wasted into the air.
• Chemical composition of the base – mild steel gives the best results. Higher carbon content decrease magnetic permeability and lifting capacity.
• Plate texture – smooth surfaces ensure maximum contact, which increases field saturation. Uneven metal weaken the grip.
• Temperature influence – hot environment weakens magnetic field. Too high temperature can permanently demagnetize the magnet.

* Lifting capacity was measured by applying a polished steel plate of suitable thickness (min. 20 mm), under vertically applied force, however under parallel forces the holding force is lower. In addition, even a small distance {between} the magnet and the plate lowers the lifting capacity.