MPL 50x20x5 / N38 - lamellar magnet

Strengths and weaknesses of rare earth magnets.

Besides their stability, neodymium magnets are valued for these benefits:

• Their power is maintained, and after approximately ten years it drops only by ~1% (theoretically),
• They do not lose their magnetic properties even under close interference source,
• The use of an elegant finish of noble metals (nickel, gold, silver) causes the element to present itself better,
• Neodymium magnets generate maximum magnetic induction on a small area, which increases force concentration,
• 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 possibility of flexible shaping and adaptation to specialized needs, NdFeB magnets can be produced in a wide range of shapes and sizes, which amplifies use scope,
• Wide application in advanced technology sectors – they find application in data components, drive modules, medical equipment, and industrial machines.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in small dimensions, which enables their usage in small systems

Disadvantages of neodymium magnets:

• At strong impacts they can break, therefore we recommend placing them in special holders. A metal housing provides additional protection against damage and increases the magnet's durability.
• NdFeB magnets lose power when exposed to high temperatures. After reaching 80°C, many of them experience permanent weakening 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 very resistant to heat
• They oxidize in a humid environment - during use outdoors we advise using waterproof magnets e.g. in rubber, plastic
• Limited possibility of making nuts in the magnet and complex shapes - preferred is a housing - magnet mounting.
• Health risk resulting from small fragments of magnets pose a threat, if swallowed, which becomes key in the aspect of protecting the youngest. It is also worth noting that small components of these magnets can disrupt the diagnostic process medical in case of swallowing.
• Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Maximum magnetic pulling force – what contributes to it?

Breakaway force was defined for optimal configuration, taking into account:

• on a plate made of structural steel, perfectly concentrating the magnetic flux
• possessing a massiveness of min. 10 mm to avoid saturation
• characterized by smoothness
• under conditions of gap-free contact (metal-to-metal)
• under perpendicular force vector (90-degree angle)
• at temperature room level

Practical aspects of lifting capacity – factors

It is worth knowing that the magnet holding will differ depending on elements below, in order of importance:

• Gap between magnet and steel – even a fraction of a millimeter of distance (caused e.g. by varnish or unevenness) significantly weakens the magnet efficiency, often by half at just 0.5 mm.
• Force direction – remember that the magnet holds strongest perpendicularly. Under sliding down, the capacity drops drastically, often to levels of 20-30% of the maximum value.
• Substrate thickness – to utilize 100% power, the steel must be sufficiently thick. Paper-thin metal limits the attraction force (the magnet "punches through" it).
• Steel grade – the best choice is pure iron steel. Stainless steels may have worse magnetic properties.
• Surface condition – ground elements ensure maximum contact, which increases force. Rough surfaces weaken the grip.
• Temperature influence – hot environment reduces magnetic field. Too high temperature can permanently damage the magnet.

* Lifting capacity testing was carried out on a smooth plate of optimal thickness, under perpendicular forces, whereas under attempts to slide the magnet the lifting capacity is smaller. In addition, even a small distance {between} the magnet and the plate lowers the holding force.