NCM 15x13.5x5 / N38 - channel magnetic holder

Advantages as well as disadvantages of NdFeB magnets.

Besides their high retention, neodymium magnets are valued for these benefits:

• They retain full power for nearly ten years – the drop is just ~1% (in theory),
• Neodymium magnets are distinguished by highly resistant to magnetic field loss caused by external field sources,
• A magnet with a shiny gold surface looks better,
• Neodymium magnets achieve maximum magnetic induction on a their surface, which ensures high operational effectiveness,
• Due to their durability and thermal resistance, neodymium magnets are capable of operate (depending on the form) even at high temperatures reaching 230°C or more...
• Due to the possibility of accurate shaping and adaptation to custom projects, NdFeB magnets can be modeled in a variety of shapes and sizes, which makes them more universal,
• Universal use in high-tech industry – they are commonly used in magnetic memories, drive modules, medical equipment, also technologically advanced constructions.
• Thanks to concentrated force, small magnets offer high operating force, occupying minimum space,

Disadvantages of NdFeB magnets:

• To avoid cracks under impact, we suggest using special steel housings. Such a solution secures the magnet and simultaneously increases its durability.
• When exposed to high temperature, neodymium magnets experience a drop in strength. Often, when the temperature exceeds 80°C, their power decreases (depending on the size and shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
• Due to the susceptibility of magnets to corrosion in a humid environment, we recommend using waterproof magnets made of rubber, plastic or other material resistant to moisture, in case of application outdoors
• We suggest cover - magnetic holder, due to difficulties in realizing threads inside the magnet and complicated forms.
• Potential hazard related to microscopic parts of magnets pose a threat, in case of ingestion, which is particularly important in the aspect of protecting the youngest. Additionally, small components of these devices are able to complicate diagnosis medical in case of swallowing.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

Maximum holding power of the magnet – what affects it?

Information about lifting capacity is the result of a measurement for the most favorable conditions, including:

• using a plate made of high-permeability steel, functioning as a circuit closing element
• whose thickness reaches at least 10 mm
• with an polished contact surface
• without the slightest air gap between the magnet and steel
• under perpendicular force vector (90-degree angle)
• at temperature approx. 20 degrees Celsius

Lifting capacity in real conditions – factors

In practice, the actual holding force depends on a number of factors, presented from crucial:

• Gap between magnet and steel – every millimeter of distance (caused e.g. by varnish or unevenness) drastically reduces the magnet efficiency, often by half at just 0.5 mm.
• Direction of force – maximum parameter is available only during pulling at a 90° angle. The force required to slide of the magnet along the surface is usually several times smaller (approx. 1/5 of the lifting capacity).
• Wall thickness – the thinner the sheet, the weaker the hold. Magnetic flux penetrates through instead of generating force.
• Material type – the best choice is pure iron steel. Stainless steels may have worse magnetic properties.
• Plate texture – ground elements guarantee perfect abutment, which improves field saturation. Rough surfaces reduce efficiency.
• Thermal factor – hot environment weakens magnetic field. Exceeding the limit temperature can permanently demagnetize the magnet.

* Lifting capacity was measured with the use of a polished steel plate of suitable thickness (min. 20 mm), under perpendicular pulling force, in contrast under shearing force the lifting capacity is smaller. Additionally, even a small distance {between} the magnet’s surface and the plate lowers the load capacity.