UMP 107x40 [M8+M10] GW F400 Lina / N38 - search holder

Strengths and weaknesses of NdFeB magnets.

Besides their high retention, neodymium magnets are valued for these benefits:

• They have stable power, and over more than ten years their performance decreases symbolically – ~1% (in testing),
• They are extremely resistant to demagnetization induced by external field influence,
• The use of an elegant finish of noble metals (nickel, gold, silver) causes the element to present itself better,
• The surface of neodymium magnets generates a unique magnetic field – this is one of their assets,
• Neodymium magnets are characterized by extremely high magnetic induction on the magnet surface and can work (depending on the shape) even at a temperature of 230°C or more...
• Possibility of custom creating and optimizing to complex conditions,
• Significant place in high-tech industry – they find application in magnetic memories, electromotive mechanisms, medical devices, also complex engineering applications.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

What to avoid - cons of neodymium magnets: weaknesses and usage proposals

• To avoid cracks upon strong impacts, we recommend using special steel holders. Such a solution secures the magnet and simultaneously improves its durability.
• Neodymium magnets lose power when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop of strength (a factor is the shape as well as 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
• Magnets exposed to a humid environment can rust. Therefore when using outdoors, we recommend using waterproof magnets made of rubber, plastic or other material resistant to moisture
• We recommend cover - magnetic mechanism, due to difficulties in creating threads inside the magnet and complex shapes.
• Potential hazard related to microscopic parts of magnets pose a threat, if swallowed, which becomes key in the context of child health protection. It is also worth noting that small elements of these products are able to complicate diagnosis medical in case of swallowing.
• With mass production the cost of neodymium magnets can be a barrier,

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

The load parameter shown refers to the maximum value, measured under ideal test conditions, namely:

• using a sheet made of high-permeability steel, acting as a magnetic yoke
• possessing a thickness of minimum 10 mm to avoid saturation
• with a plane cleaned and smooth
• without any air gap between the magnet and steel
• for force applied at a right angle (pull-off, not shear)
• at room temperature

Practical lifting capacity: influencing factors

Effective lifting capacity is influenced by specific conditions, including (from most important):

• Air gap (betwixt the magnet and the metal), since even a tiny clearance (e.g. 0.5 mm) can cause a reduction in force by up to 50% (this also applies to varnish, rust or dirt).
• Load vector – maximum parameter is obtained only during pulling at a 90° angle. The force required to slide of the magnet along the surface is usually several times lower (approx. 1/5 of the lifting capacity).
• Element thickness – for full efficiency, the steel must be adequately massive. Paper-thin metal limits the lifting capacity (the magnet "punches through" it).
• Steel grade – ideal substrate is pure iron steel. Hardened steels may have worse magnetic properties.
• Plate texture – ground elements guarantee perfect abutment, which improves field saturation. Uneven metal reduce efficiency.
• Thermal conditions – neodymium magnets have a negative temperature coefficient. At higher temperatures they lose power, and in frost they can be stronger (up to a certain limit).

* Lifting capacity was measured with the use of a polished steel plate of suitable thickness (min. 20 mm), under perpendicular detachment force, however under shearing force the holding force is lower. Additionally, even a small distance {between} the magnet and the plate lowers the load capacity.