UMP 75x25 [M10x3] GW F200 PLATINIUM / N52 - search holder

Advantages and disadvantages of rare earth magnets.

Besides their tremendous pulling force, neodymium magnets offer the following advantages:

• They virtually do not lose strength, because even after ten years the decline in efficiency is only ~1% (in laboratory conditions),
• They are resistant to demagnetization induced by presence of other magnetic fields,
• By using a shiny coating of nickel, the element gains an aesthetic look,
• They are known for high magnetic induction at the operating surface, which improves attraction properties,
• Through (appropriate) combination of ingredients, they can achieve high thermal strength, allowing for operation at temperatures reaching 230°C and above...
• Possibility of custom creating and adapting to defined conditions,
• Universal use in high-tech industry – they are utilized in mass storage devices, electric motors, precision medical tools, and other advanced devices.
• Compactness – despite small sizes they provide effective action, making them ideal for precision applications

Disadvantages of NdFeB magnets:

• They are prone to damage upon too strong impacts. To avoid cracks, it is worth securing magnets in a protective case. Such protection not only protects the magnet but also improves its resistance to damage
• Neodymium magnets lose force when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop of power (a factor is the shape and dimensions of the magnet). We offer magnets specially adapted to work at temperatures up to 230°C marked [AH], which are very resistant to heat
• They rust in a humid environment. For use outdoors we advise using waterproof magnets e.g. in rubber, plastic
• We suggest a housing - magnetic mechanism, due to difficulties in realizing nuts inside the magnet and complex shapes.
• Health risk resulting from small fragments of magnets are risky, when accidentally swallowed, which is particularly important in the context of child health protection. It is also worth noting that tiny parts of these magnets are able to disrupt the diagnostic process medical after entering the body.
• Due to neodymium price, their price exceeds standard values,

Maximum magnetic pulling force – what contributes to it?

Breakaway force is the result of a measurement for optimal configuration, including:

• on a base made of structural steel, effectively closing the magnetic field
• with a cross-section no less than 10 mm
• characterized by even structure
• under conditions of no distance (metal-to-metal)
• during detachment in a direction perpendicular to the plane
• at room temperature

Lifting capacity in practice – influencing factors

During everyday use, the actual holding force is determined by many variables, listed from crucial:

• Gap (between the magnet and the plate), as even a tiny distance (e.g. 0.5 mm) results in a reduction in lifting capacity by up to 50% (this also applies to varnish, corrosion or dirt).
• Angle of force application – maximum parameter is reached only during perpendicular pulling. The resistance to sliding of the magnet along the surface is standardly many times lower (approx. 1/5 of the lifting capacity).
• Metal thickness – thin material does not allow full use of the magnet. Part of the magnetic field passes through the material instead of converting into lifting capacity.
• Metal type – different alloys reacts the same. High carbon content worsen the interaction with the magnet.
• Surface finish – ideal contact is obtained only on polished steel. Rough texture reduce the real contact area, reducing force.
• Thermal factor – high temperature reduces pulling force. Too high temperature can permanently demagnetize the magnet.

* Lifting capacity was assessed with the use of a polished steel plate of optimal thickness (min. 20 mm), under vertically applied force, whereas under shearing force the holding force is lower. Additionally, even a slight gap {between} the magnet’s surface and the plate reduces the load capacity.