UMP 107x40 [M8+M10] GW F 400 kg / N38 - search holder

Advantages and disadvantages of neodymium magnets.

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

• They do not lose magnetism, even over around 10 years – the reduction in lifting capacity is only ~1% (based on measurements),
• Neodymium magnets are highly resistant to magnetic field loss caused by magnetic disturbances,
• A magnet with a metallic gold surface looks better,
• They feature high magnetic induction at the operating surface, making them more effective,
• Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their shape) at temperatures up to 230°C and above...
• Possibility of detailed modeling and optimizing to individual needs,
• Wide application in future technologies – they are used in mass storage devices, drive modules, medical equipment, as well as complex engineering applications.
• Thanks to concentrated force, small magnets offer high operating force, occupying minimum space,

Problematic aspects of neodymium magnets and proposals for their use:

• To avoid cracks upon strong impacts, we suggest using special steel holders. Such a solution protects the magnet and simultaneously increases its durability.
• When exposed to high temperature, neodymium magnets suffer a drop in strength. Often, when the temperature exceeds 80°C, their power 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
• They rust in a humid environment. For use outdoors we recommend using waterproof magnets e.g. in rubber, plastic
• We suggest cover - magnetic mount, due to difficulties in producing nuts inside the magnet and complicated shapes.
• Health risk related to microscopic parts of magnets are risky, if swallowed, which becomes key in the aspect of protecting the youngest. It is also worth noting that tiny parts of these magnets are able to disrupt the diagnostic process medical after entering the body.
• Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Maximum lifting force for a neodymium magnet – what it depends on?

Breakaway force is the result of a measurement for the most favorable conditions, taking into account:

• with the contact of a sheet made of special test steel, ensuring full magnetic saturation
• possessing a thickness of min. 10 mm to avoid saturation
• with a plane perfectly flat
• with zero gap (no coatings)
• under axial application of breakaway force (90-degree angle)
• in temp. approx. 20°C

What influences lifting capacity in practice

Real force impacted by specific conditions, including (from most important):

• Clearance – existence of any layer (paint, tape, gap) interrupts the magnetic circuit, which reduces power steeply (even by 50% at 0.5 mm).
• Direction of force – maximum parameter is obtained only during perpendicular pulling. The shear force of the magnet along the plate is standardly many times lower (approx. 1/5 of the lifting capacity).
• Element thickness – for full efficiency, the steel must be adequately massive. Paper-thin metal restricts the lifting capacity (the magnet "punches through" it).
• Metal type – different alloys attracts identically. High carbon content worsen the interaction with the magnet.
• Surface quality – the more even the surface, the larger the contact zone and higher the lifting capacity. Roughness acts like micro-gaps.
• Temperature – heating the magnet results in weakening of force. Check the thermal limit for a given model.

* Holding force was measured on the plate surface of 20 mm thickness, when the force acted perpendicularly, in contrast under attempts to slide the magnet the lifting capacity is smaller. Moreover, even a slight gap {between} the magnet’s surface and the plate lowers the load capacity.