NCM 40x13.5x5 / N38 - channel magnetic holder

Pros and cons of NdFeB magnets.

Besides their remarkable pulling force, neodymium magnets offer the following advantages:

• They have stable power, and over more than ten years their attraction force decreases symbolically – ~1% (according to theory),
• They have excellent resistance to magnetic field loss as a result of external magnetic sources,
• By using a smooth layer of nickel, the element has an professional look,
• The surface of neodymium magnets generates a strong magnetic field – this is a distinguishing feature,
• Neodymium magnets are characterized by extremely high magnetic induction on the magnet surface and can work (depending on the shape) even at a temperature of 230°C or more...
• Thanks to versatility in designing and the capacity to modify to client solutions,
• Versatile presence in electronics industry – they serve a role in data components, electric drive systems, advanced medical instruments, and modern systems.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

Drawbacks and weaknesses of neodymium magnets: weaknesses and usage proposals

• They are fragile upon too strong impacts. To avoid cracks, it is worth protecting magnets using a steel holder. Such protection not only shields the magnet but also increases its resistance to damage
• Neodymium magnets demagnetize when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop of power (a factor is the shape as well as 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
• Due to the susceptibility of magnets to corrosion in a humid environment, we recommend using waterproof magnets made of rubber, plastic or other material immune to moisture, in case of application outdoors
• Limited ability of creating threads in the magnet and complicated shapes - preferred is cover - magnet mounting.
• Health risk resulting from small fragments of magnets are risky, in case of ingestion, which gains importance in the context of child safety. It is also worth noting that tiny parts of these magnets are able to complicate diagnosis medical after entering the body.
• With large orders the cost of neodymium magnets can be a barrier,

Detachment force of the magnet in optimal conditions – what affects it?

Magnet power is the result of a measurement for the most favorable conditions, including:

• with the application of a sheet made of special test steel, ensuring full magnetic saturation
• whose thickness is min. 10 mm
• characterized by smoothness
• with direct contact (no coatings)
• during pulling in a direction perpendicular to the plane
• in stable room temperature

Practical aspects of lifting capacity – factors

Effective lifting capacity is affected by working environment parameters, mainly (from most important):

• Distance (between the magnet and the plate), as even a tiny clearance (e.g. 0.5 mm) can cause a reduction in lifting capacity by up to 50% (this also applies to paint, rust or debris).
• Angle of force application – maximum parameter is reached only during perpendicular pulling. The force required to slide of the magnet along the surface is standardly many times lower (approx. 1/5 of the lifting capacity).
• Element thickness – for full efficiency, the steel must be adequately massive. Thin sheet limits the lifting capacity (the magnet "punches through" it).
• Plate material – low-carbon steel gives the best results. Alloy steels reduce magnetic properties and lifting capacity.
• Surface condition – ground elements guarantee perfect abutment, which increases force. Rough surfaces weaken the grip.
• Operating temperature – NdFeB sinters have a negative temperature coefficient. At higher temperatures they lose power, and in frost they can be stronger (up to a certain limit).

* Holding force was tested on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, whereas under parallel forces the holding force is lower. In addition, even a slight gap {between} the magnet and the plate reduces the holding force.