UMH 48x11x65 [M6] / N38 - magnetic holder with hook

Pros as well as cons of neodymium magnets.

Apart from their notable magnetism, neodymium magnets have these key benefits:

• Their strength is durable, and after approximately 10 years it drops only by ~1% (according to research),
• Neodymium magnets are highly resistant to demagnetization caused by external field sources,
• Thanks to the elegant finish, the surface of Ni-Cu-Ni, gold-plated, or silver gives an elegant appearance,
• Magnetic induction on the working part of the magnet turns out to be very high,
• Neodymium magnets are characterized by extremely 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 freedom in shaping and the ability to adapt to individual projects,
• Key role in electronics industry – they find application in HDD drives, brushless drives, diagnostic systems, also modern systems.
• Thanks to efficiency per cm³, small magnets offer high operating force, in miniature format,

Disadvantages of neodymium magnets:

• To avoid cracks upon strong impacts, we suggest using special steel holders. Such a solution secures the magnet and simultaneously improves its durability.
• When exposed to high temperature, neodymium magnets suffer a drop in force. Often, when the temperature exceeds 80°C, their strength decreases (depending on the size and 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 while using outdoors, we suggest using waterproof magnets made of rubber, plastic or other material resistant to moisture
• We suggest a housing - magnetic mechanism, due to difficulties in realizing threads inside the magnet and complex shapes.
• Possible danger to health – tiny shards of magnets can be dangerous, when accidentally swallowed, which gains importance in the context of child health protection. Furthermore, tiny parts of these devices can complicate diagnosis medical after entering the body.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

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

The specified lifting capacity concerns the limit force, recorded under optimal environment, specifically:

• with the use of a yoke made of special test steel, guaranteeing full magnetic saturation
• possessing a thickness of at least 10 mm to avoid saturation
• characterized by lack of roughness
• under conditions of no distance (surface-to-surface)
• for force acting at a right angle (pull-off, not shear)
• at conditions approx. 20°C

Practical aspects of lifting capacity – factors

In real-world applications, the real power results from many variables, listed from the most important:

• Clearance – existence of any layer (rust, tape, gap) acts as an insulator, which reduces capacity steeply (even by 50% at 0.5 mm).
• Pull-off angle – remember that the magnet has greatest strength perpendicularly. Under sliding down, the capacity drops drastically, often to levels of 20-30% of the maximum value.
• Metal thickness – the thinner the sheet, the weaker the hold. Part of the magnetic field penetrates through instead of generating force.
• Chemical composition of the base – mild steel attracts best. Higher carbon content lower magnetic properties and holding force.
• Surface condition – smooth surfaces ensure maximum contact, which improves field saturation. Uneven metal reduce efficiency.
• Temperature influence – high temperature weakens magnetic field. Exceeding the limit temperature can permanently demagnetize the magnet.

* Lifting capacity was determined by applying a steel plate with a smooth surface of suitable thickness (min. 20 mm), under vertically applied force, in contrast under parallel forces the load capacity is reduced by as much as 5 times. Additionally, even a slight gap {between} the magnet’s surface and the plate decreases the lifting capacity.