MW 8x1.5 / N38 - cylindrical magnet

Strengths as well as weaknesses of NdFeB magnets.

Besides their magnetic performance, neodymium magnets are valued for these benefits:

• They retain full power for nearly ten years – the loss is just ~1% (according to analyses),
• Magnets effectively protect themselves against loss of magnetization caused by ambient magnetic noise,
• By using a reflective layer of nickel, the element acquires an elegant look,
• Magnetic induction on the working layer of the magnet remains impressive,
• Thanks to resistance to high temperature, they are able to function (depending on the shape) even at temperatures up to 230°C and higher...
• Possibility of individual machining as well as optimizing to specific needs,
• Huge importance in electronics industry – they find application in computer drives, electric motors, diagnostic systems, as well as technologically advanced constructions.
• Thanks to concentrated force, small magnets offer high operating force, with minimal size,

Disadvantages of neodymium magnets:

• To avoid cracks under impact, we suggest using special steel holders. Such a solution protects the magnet and simultaneously improves its durability.
• We warn that neodymium magnets can lose their power at high temperatures. To prevent this, we recommend our specialized [AH] magnets, which work effectively even at 230°C.
• Due to the susceptibility of magnets to corrosion in a humid environment, we suggest using waterproof magnets made of rubber, plastic or other material resistant to moisture, when using outdoors
• Due to limitations in producing threads and complex shapes in magnets, we recommend using a housing - magnetic holder.
• Potential hazard to health – tiny shards of magnets can be dangerous, when accidentally swallowed, which is particularly important in the context of child health protection. Additionally, tiny parts of these devices are able to complicate diagnosis medical in case of swallowing.
• With large orders the cost of neodymium magnets is economically unviable,

Maximum lifting capacity of the magnet – what it depends on?

The force parameter is a measurement result executed under the following configuration:

• with the application of a sheet made of low-carbon steel, ensuring full magnetic saturation
• whose thickness reaches at least 10 mm
• with an polished contact surface
• with total lack of distance (no coatings)
• during detachment in a direction vertical to the plane
• in neutral thermal conditions

Impact of factors on magnetic holding capacity in practice

Effective lifting capacity is affected by specific conditions, mainly (from most important):

• Gap (betwixt the magnet and the metal), because even a very small distance (e.g. 0.5 mm) leads to a reduction in lifting capacity by up to 50% (this also applies to varnish, rust or debris).
• Direction of force – maximum parameter is available only during pulling at a 90° angle. The force required to slide of the magnet along the plate is typically several times smaller (approx. 1/5 of the lifting capacity).
• Plate thickness – insufficiently thick steel causes magnetic saturation, causing part of the flux to be lost to the other side.
• Plate material – low-carbon steel gives the best results. Alloy steels reduce magnetic permeability and lifting capacity.
• Plate texture – smooth surfaces guarantee perfect abutment, which increases force. Rough surfaces weaken the grip.
• Thermal conditions – NdFeB sinters have a negative temperature coefficient. At higher temperatures they are weaker, and at low temperatures gain strength (up to a certain limit).

* Lifting capacity was assessed with the use of a smooth steel plate of suitable thickness (min. 20 mm), under vertically applied force, in contrast under parallel forces the holding force is lower. Moreover, even a minimal clearance {between} the magnet’s surface and the plate decreases the lifting capacity.