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

Pros and cons of NdFeB magnets.

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

• They retain attractive force for nearly 10 years – the drop is just ~1% (according to analyses),
• Neodymium magnets are extremely resistant to magnetic field loss caused by external magnetic fields,
• In other words, due to the glossy surface of nickel, the element is aesthetically pleasing,
• Magnetic induction on the working part of the magnet turns out to be extremely intense,
• Due to their durability and thermal resistance, neodymium magnets can operate (depending on the shape) even at high temperatures reaching 230°C or more...
• Thanks to freedom in forming and the capacity to customize to specific needs,
• Versatile presence in modern industrial fields – they serve a role in computer drives, electric motors, precision medical tools, as well as multitasking production systems.
• Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications

Characteristics of disadvantages of neodymium magnets and ways of using them

• To avoid cracks under impact, we suggest using special steel holders. Such a solution protects the magnet and simultaneously increases its durability.
• 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
• They rust in a humid environment - during use outdoors we recommend using waterproof magnets e.g. in rubber, plastic
• Due to limitations in creating nuts and complex forms in magnets, we propose using cover - magnetic holder.
• Health risk resulting from small fragments of magnets are risky, if swallowed, which gains importance in the context of child health protection. Additionally, small elements of these devices can be problematic in diagnostics medical after entering the body.
• Due to expensive raw materials, their price is relatively high,

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

The specified lifting capacity represents the peak performance, measured under ideal test conditions, specifically:

• with the application of a yoke made of low-carbon steel, guaranteeing maximum field concentration
• whose thickness equals approx. 10 mm
• with a surface perfectly flat
• without the slightest insulating layer between the magnet and steel
• under perpendicular application of breakaway force (90-degree angle)
• at room temperature

What influences lifting capacity in practice

In practice, the actual holding force is determined by several key aspects, presented from most significant:

• Space between magnet and steel – even a fraction of a millimeter of separation (caused e.g. by veneer or dirt) significantly weakens the magnet efficiency, often by half at just 0.5 mm.
• Loading method – declared lifting capacity refers to detachment vertically. When applying parallel force, the magnet holds much less (typically approx. 20-30% of nominal force).
• Plate thickness – insufficiently thick plate does not close the flux, causing part of the power to be lost to the other side.
• Material type – ideal substrate is pure iron steel. Cast iron may generate lower lifting capacity.
• Surface finish – full contact is obtained only on smooth steel. Any scratches and bumps reduce the real contact area, weakening the magnet.
• Thermal factor – hot environment reduces magnetic field. Exceeding the limit temperature can permanently damage the magnet.

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