MP 5x2.7/1.2x5 C / N38 - ring magnet

Pros and cons of rare earth magnets.

In addition to their magnetic efficiency, neodymium magnets provide the following advantages:

• They retain magnetic properties for nearly ten years – the loss is just ~1% (according to analyses),
• They feature excellent resistance to weakening of magnetic properties due to opposing magnetic fields,
• The use of an refined finish of noble metals (nickel, gold, silver) causes the element to have aesthetics,
• The surface of neodymium magnets generates a concentrated magnetic field – this is a key feature,
• Due to their durability and thermal resistance, neodymium magnets can operate (depending on the shape) even at high temperatures reaching 230°C or more...
• Thanks to the ability of free shaping and customization to custom requirements, magnetic components can be modeled in a wide range of forms and dimensions, which amplifies use scope,
• Key role in future technologies – they are used in computer drives, drive modules, medical devices, as well as multitasking production systems.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in small dimensions, which makes them useful in small systems

Disadvantages of NdFeB magnets:

• To avoid cracks upon strong impacts, we recommend using special steel housings. Such a solution secures the magnet and simultaneously increases its durability.
• NdFeB magnets lose force when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop of strength (a factor is the shape and dimensions of the magnet). We offer magnets specially adapted to work at temperatures up to 230°C marked [AH], which are extremely resistant to heat
• Magnets exposed to a humid environment can corrode. Therefore when using outdoors, we suggest using waterproof magnets made of rubber, plastic or other material protecting against moisture
• We suggest a housing - magnetic mount, due to difficulties in producing nuts inside the magnet and complex shapes.
• Potential hazard related to microscopic parts of magnets are risky, in case of ingestion, which becomes key in the context of child health protection. It is also worth noting that small elements of these products can disrupt the diagnostic process medical after entering the body.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

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

The specified lifting capacity concerns the peak performance, measured under ideal test conditions, namely:

• on a plate made of structural steel, effectively closing the magnetic field
• possessing a thickness of at least 10 mm to ensure full flux closure
• with a surface perfectly flat
• under conditions of gap-free contact (metal-to-metal)
• under vertical force vector (90-degree angle)
• at conditions approx. 20°C

Practical aspects of lifting capacity – factors

Bear in mind that the magnet holding may be lower influenced by the following factors, starting with the most relevant:

• Distance – the presence of any layer (rust, dirt, air) interrupts the magnetic circuit, which reduces capacity steeply (even by 50% at 0.5 mm).
• Loading method – catalog parameter refers to detachment vertically. When slipping, the magnet exhibits significantly lower power (often approx. 20-30% of nominal force).
• Wall thickness – thin material does not allow full use of the magnet. Part of the magnetic field penetrates through instead of generating force.
• Steel type – low-carbon steel attracts best. Alloy steels decrease magnetic permeability and holding force.
• Surface finish – full contact is possible only on polished steel. Any scratches and bumps reduce the real contact area, weakening the magnet.
• Thermal environment – heating the magnet results in weakening of induction. Check the maximum operating temperature for a given model.

* Lifting capacity was determined using a polished steel plate of suitable thickness (min. 20 mm), under vertically applied force, in contrast under parallel forces the lifting capacity is smaller. Additionally, even a small distance {between} the magnet and the plate lowers the lifting capacity.