UMP 75x24 [M8+M10] GW F 200 kg - search holder

Strengths and weaknesses of neodymium magnets.

Besides their magnetic performance, neodymium magnets are valued for these benefits:

• They retain full power for nearly ten years – the loss is just ~1% (according to analyses),
• They do not lose their magnetic properties even under close interference source,
• Thanks to the shimmering finish, the coating of Ni-Cu-Ni, gold, or silver gives an modern appearance,
• Magnets have huge magnetic induction on the surface,
• 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 flexibility in shaping and the ability to customize to client solutions,
• Wide application in modern technologies – they find application in mass storage devices, brushless drives, medical devices, also industrial machines.
• Thanks to efficiency per cm³, small magnets offer high operating force, occupying minimum space,

Characteristics of disadvantages of neodymium magnets: weaknesses and usage proposals

• At strong impacts they can crack, therefore we advise placing them in strong housings. A metal housing provides additional protection against damage, as well as 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 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 secure oxidation and corrosion.
• Limited possibility of creating nuts in the magnet and complicated forms - recommended is cover - magnetic holder.
• Health risk resulting from small fragments of magnets are risky, if swallowed, which becomes key in the aspect of protecting the youngest. Furthermore, small elements of these products can complicate diagnosis medical after entering the body.
• Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Breakaway strength of the magnet in ideal conditions – what it depends on?

Breakaway force was defined for ideal contact conditions, including:

• on a block made of mild steel, perfectly concentrating the magnetic field
• possessing a thickness of minimum 10 mm to avoid saturation
• characterized by even structure
• without any insulating layer between the magnet and steel
• under vertical force direction (90-degree angle)
• at room temperature

Determinants of lifting force in real conditions

In practice, the actual lifting capacity depends on several key aspects, presented from crucial:

• Space between surfaces – even a fraction of a millimeter of distance (caused e.g. by varnish or unevenness) diminishes the magnet efficiency, often by half at just 0.5 mm.
• Force direction – note that the magnet holds strongest perpendicularly. Under shear forces, the holding force drops significantly, often to levels of 20-30% of the maximum value.
• Wall thickness – the thinner the sheet, the weaker the hold. Magnetic flux penetrates through instead of converting into lifting capacity.
• Material composition – not every steel attracts identically. Alloy additives weaken the attraction effect.
• Surface quality – the more even the surface, the better the adhesion and stronger the hold. Roughness acts like micro-gaps.
• Temperature – temperature increase causes a temporary drop of force. Check the maximum operating temperature for a given model.

* Lifting capacity testing was conducted on a smooth plate of optimal thickness, under a perpendicular pulling force, however under attempts to slide the magnet the holding force is lower. Additionally, even a small distance {between} the magnet and the plate decreases the load capacity.