UMGZ 20x15x7 [M4] GZ / N38 - magnetic holder external thread

Pros as well as cons of rare earth magnets.

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

• Their magnetic field remains stable, and after around 10 years it drops only by ~1% (according to research),
• They show high resistance to demagnetization induced by presence of other magnetic fields,
• Thanks to the smooth finish, the layer of Ni-Cu-Ni, gold-plated, or silver gives an clean appearance,
• Magnetic induction on the top side of the magnet is strong,
• Neodymium magnets are characterized by very high magnetic induction on the magnet surface and can function (depending on the shape) even at a temperature of 230°C or more...
• Thanks to freedom in shaping and the capacity to customize to unusual requirements,
• Key role in innovative solutions – they are utilized in mass storage devices, electric motors, diagnostic systems, and technologically advanced constructions.
• Relatively small size with high pulling force – neodymium magnets offer high power in compact dimensions, which makes them useful in miniature devices

Disadvantages of neodymium magnets:

• They are fragile upon heavy impacts. To avoid cracks, it is worth securing magnets using a steel holder. Such protection not only shields the magnet but also improves its resistance to damage
• We warn that neodymium magnets can reduce their strength at high temperatures. To prevent this, we recommend our specialized [AH] magnets, which work effectively even at 230°C.
• Magnets exposed to a humid environment can corrode. Therefore during using outdoors, we advise using waterproof magnets made of rubber, plastic or other material protecting against moisture
• Due to limitations in producing nuts 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 gains importance in the aspect of protecting the youngest. It is also worth noting that small elements of these magnets can complicate diagnosis medical after entering the body.
• Due to neodymium price, their price is relatively high,

Breakaway strength of the magnet in ideal conditions – what contributes to it?

The force parameter is a result of laboratory testing conducted under standard conditions:

• on a block made of mild steel, optimally conducting the magnetic field
• whose transverse dimension is min. 10 mm
• with an ground touching surface
• under conditions of gap-free contact (surface-to-surface)
• under axial force direction (90-degree angle)
• in neutral thermal conditions

Key elements affecting lifting force

Real force is influenced by working environment parameters, mainly (from priority):

• Gap (between the magnet and the metal), as even a microscopic distance (e.g. 0.5 mm) leads to a decrease in force by up to 50% (this also applies to paint, corrosion or dirt).
• Loading method – catalog parameter refers to detachment vertically. When applying parallel force, the magnet exhibits much less (typically approx. 20-30% of nominal force).
• Element thickness – for full efficiency, the steel must be sufficiently thick. Paper-thin metal limits the attraction force (the magnet "punches through" it).
• Steel grade – the best choice is high-permeability steel. Cast iron may attract less.
• Surface finish – ideal contact is obtained only on smooth steel. Any scratches and bumps reduce the real contact area, weakening the magnet.
• Temperature influence – hot environment reduces magnetic field. Exceeding the limit temperature can permanently demagnetize the magnet.

* Lifting capacity testing was carried out on plates with a smooth surface of optimal thickness, under a perpendicular pulling force, in contrast under parallel forces the holding force is lower. In addition, even a minimal clearance {between} the magnet’s surface and the plate reduces the load capacity.