UMP 75x25 [M10x3] GW F200 GOLD Lina / N42 - search holder

Strengths as well as weaknesses of NdFeB magnets.

In addition to their long-term stability, neodymium magnets provide the following advantages:

• They have constant strength, and over nearly 10 years their performance decreases symbolically – ~1% (in testing),
• Neodymium magnets prove to be remarkably resistant to loss of magnetic properties caused by external field sources,
• The use of an refined coating of noble metals (nickel, gold, silver) causes the element to have aesthetics,
• The surface of neodymium magnets generates a intense magnetic field – this is a distinguishing feature,
• Thanks to resistance to high temperature, they are capable of working (depending on the shape) even at temperatures up to 230°C and higher...
• Possibility of exact creating as well as adjusting to atypical conditions,
• Versatile presence in modern technologies – they find application in hard drives, electric motors, precision medical tools, as well as complex engineering applications.
• Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in compact dimensions, which makes them useful in miniature devices

Disadvantages of neodymium magnets:

• Brittleness is one of their disadvantages. Upon strong impact they can break. We recommend keeping them in a strong case, which not only secures them against impacts but also increases their durability
• 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, as well as shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
• When exposed to humidity, magnets start to rust. To use them in conditions outside, it is recommended to use protective magnets, such as those in rubber or plastics, which secure oxidation as well as corrosion.
• Limited possibility of producing threads in the magnet and complicated shapes - preferred is a housing - mounting mechanism.
• Health risk to health – tiny shards of magnets can be dangerous, if swallowed, which becomes key in the aspect of protecting the youngest. It is also worth noting that small elements of these devices can complicate diagnosis medical after entering the body.
• With large orders the cost of neodymium magnets is a challenge,

Highest magnetic holding force – what it depends on?

The declared magnet strength refers to the maximum value, measured under optimal environment, namely:

• on a block made of structural steel, optimally conducting the magnetic field
• whose thickness reaches at least 10 mm
• with a surface free of scratches
• under conditions of ideal adhesion (metal-to-metal)
• for force acting at a right angle (pull-off, not shear)
• at room temperature

Lifting capacity in practice – influencing factors

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

• Distance – existence of foreign body (paint, dirt, gap) interrupts the magnetic circuit, which lowers power steeply (even by 50% at 0.5 mm).
• Direction of force – highest force is obtained only during pulling at a 90° angle. The shear force of the magnet along the surface is standardly several times smaller (approx. 1/5 of the lifting capacity).
• Element thickness – for full efficiency, the steel must be adequately massive. Paper-thin metal limits the attraction force (the magnet "punches through" it).
• Material composition – not every steel attracts identically. High carbon content worsen the attraction effect.
• Plate texture – smooth surfaces ensure maximum contact, which improves field saturation. Rough surfaces weaken the grip.
• Thermal conditions – NdFeB sinters have a sensitivity to temperature. At higher temperatures they are weaker, and in frost they can be stronger (up to a certain limit).

* Lifting capacity was assessed with the use of a polished steel plate of optimal thickness (min. 20 mm), under vertically applied force, however under attempts to slide the magnet the lifting capacity is smaller. Additionally, even a minimal clearance {between} the magnet and the plate lowers the load capacity.