HH 42x8.8 [M6] / N38 - through hole magnetic holder

Pros and cons of neodymium magnets.

Besides their tremendous field intensity, neodymium magnets offer the following advantages:

• Their strength remains stable, and after approximately 10 years it decreases only by ~1% (according to research),
• Magnets perfectly protect themselves against demagnetization caused by ambient magnetic noise,
• The use of an refined layer of noble metals (nickel, gold, silver) causes the element to present itself better,
• Magnetic induction on the surface of the magnet turns out to be maximum,
• Due to their durability and thermal resistance, neodymium magnets can operate (depending on the form) even at high temperatures reaching 230°C or more...
• Thanks to the option of flexible shaping and customization to custom solutions, magnetic components can be manufactured in a variety of shapes and sizes, which amplifies use scope,
• Huge importance in modern industrial fields – they find application in mass storage devices, electric drive systems, medical equipment, also complex engineering applications.
• Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in small dimensions, which enables their usage in compact constructions

Cons of neodymium magnets: application proposals

• Susceptibility to cracking is one of their disadvantages. Upon strong impact they can fracture. We recommend keeping them in a steel housing, which not only protects them against impacts but also increases their durability
• When exposed to high temperature, neodymium magnets suffer a drop in strength. Often, when the temperature exceeds 80°C, their strength 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 usually rust. To use them in conditions outside, it is recommended to use protective magnets, such as those in rubber or plastics, which prevent oxidation as well as corrosion.
• Due to limitations in producing threads and complicated forms in magnets, we recommend using casing - magnetic mount.
• Possible danger resulting from small fragments of magnets pose a threat, when accidentally swallowed, which becomes key in the context of child safety. Furthermore, small elements of these devices can disrupt the diagnostic process medical in case of swallowing.
• With budget limitations the cost of neodymium magnets is a challenge,

Optimal lifting capacity of a neodymium magnet – what affects it?

Breakaway force is the result of a measurement for ideal contact conditions, assuming:

• on a plate made of mild steel, effectively closing the magnetic flux
• possessing a thickness of at least 10 mm to avoid saturation
• characterized by lack of roughness
• under conditions of ideal adhesion (surface-to-surface)
• during detachment in a direction perpendicular to the mounting surface
• at room temperature

Practical lifting capacity: influencing factors

In practice, the real power results from many variables, ranked from the most important:

• Space between magnet and steel – even a fraction of a millimeter of distance (caused e.g. by veneer or dirt) drastically reduces the magnet efficiency, often by half at just 0.5 mm.
• Pull-off angle – remember that the magnet holds strongest perpendicularly. Under shear forces, the capacity drops drastically, often to levels of 20-30% of the maximum value.
• Element thickness – to utilize 100% power, the steel must be sufficiently thick. Thin sheet limits the lifting capacity (the magnet "punches through" it).
• Material type – ideal substrate is pure iron steel. Hardened steels may generate lower lifting capacity.
• Base smoothness – the more even the plate, the better the adhesion and higher the lifting capacity. Unevenness acts like micro-gaps.
• Temperature influence – hot environment weakens magnetic field. Too high temperature can permanently demagnetize the magnet.

* Holding force was checked on the plate surface of 20 mm thickness, when the force acted perpendicularly, however under shearing force the lifting capacity is smaller. Additionally, even a slight gap {between} the magnet’s surface and the plate reduces the holding force.