UMGZ 32x18x8 [M6] GZ / N38 - magnetic holder external thread

Strengths and weaknesses of NdFeB magnets.

Apart from their consistent holding force, neodymium magnets have these key benefits:

• They virtually do not lose strength, because even after 10 years the decline in efficiency is only ~1% (according to literature),
• Neodymium magnets are characterized by remarkably resistant to magnetic field loss caused by external interference,
• Thanks to the metallic finish, the coating of nickel, gold-plated, or silver gives an professional appearance,
• Magnetic induction on the surface of the magnet is extremely intense,
• Neodymium magnets are characterized by very high magnetic induction on the magnet surface and are able to act (depending on the form) even at a temperature of 230°C or more...
• Thanks to flexibility in constructing and the capacity to adapt to client solutions,
• Key role in innovative solutions – they find application in HDD drives, electric motors, medical equipment, and modern systems.
• Relatively small size with high pulling force – neodymium magnets offer high power in small dimensions, which enables their usage in small systems

Characteristics of disadvantages of neodymium magnets: tips and applications.

• To avoid cracks upon strong impacts, we recommend using special steel housings. Such a solution secures the magnet and simultaneously improves its durability.
• When exposed to high temperature, neodymium magnets experience a drop in power. 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
• Magnets exposed to a humid environment can rust. Therefore during using outdoors, we recommend using water-impermeable magnets made of rubber, plastic or other material protecting against moisture
• Due to limitations in realizing nuts and complex forms in magnets, we propose using a housing - magnetic mechanism.
• Health risk related to microscopic parts of magnets are risky, when accidentally swallowed, which is particularly important in the context of child health protection. Additionally, small components of these devices can disrupt the diagnostic process medical when they are in the body.
• Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Maximum magnetic pulling force – what affects it?

The lifting capacity listed is a theoretical maximum value executed under specific, ideal conditions:

• with the contact of a yoke made of special test steel, ensuring full magnetic saturation
• possessing a massiveness of min. 10 mm to ensure full flux closure
• characterized by even structure
• under conditions of ideal adhesion (surface-to-surface)
• during pulling in a direction perpendicular to the plane
• in stable room temperature

Impact of factors on magnetic holding capacity in practice

Effective lifting capacity impacted by working environment parameters, including (from most important):

• Clearance – existence of any layer (rust, dirt, gap) acts as an insulator, which reduces capacity rapidly (even by 50% at 0.5 mm).
• Direction of force – highest force is reached only during perpendicular pulling. The force required to slide of the magnet along the surface is typically several times lower (approx. 1/5 of the lifting capacity).
• Steel thickness – too thin plate does not close the flux, causing part of the flux to be wasted into the air.
• Material type – the best choice is high-permeability steel. Stainless steels may have worse magnetic properties.
• Surface condition – ground elements ensure maximum contact, which improves field saturation. Uneven metal weaken the grip.
• Thermal factor – hot environment weakens pulling force. Exceeding the limit temperature can permanently demagnetize the magnet.

* Holding force was tested on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, however under attempts to slide the magnet the lifting capacity is smaller. Additionally, even a small distance {between} the magnet’s surface and the plate lowers the holding force.