AM ucho [M12] - magnetic accessories

Advantages as well as disadvantages of neodymium magnets.

Besides their remarkable strength, neodymium magnets offer the following advantages:

• They virtually do not lose strength, because even after ten years the decline in efficiency is only ~1% (based on calculations),
• They maintain their magnetic properties even under external field action,
• By applying a lustrous coating of nickel, the element has an elegant look,
• Magnets have maximum magnetic induction on the outer side,
• 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 precise shaping and adjusting to complex applications,
• Fundamental importance in electronics industry – they are commonly used in hard drives, motor assemblies, diagnostic systems, and technologically advanced constructions.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in compact dimensions, which enables their usage in small systems

Disadvantages of NdFeB magnets:

• They are prone to damage upon heavy impacts. To avoid cracks, it is worth protecting magnets in a protective case. Such protection not only shields the magnet but also improves its resistance to damage
• Neodymium magnets decrease their force under the influence of heating. As soon as 80°C is exceeded, many of them start losing their power. Therefore, we recommend our special magnets marked [AH], which maintain durability even at temperatures up to 230°C
• They oxidize in a humid environment - during use outdoors we recommend using waterproof magnets e.g. in rubber, plastic
• Due to limitations in producing threads and complicated forms in magnets, we recommend using casing - magnetic holder.
• Possible danger related to microscopic parts of magnets pose a threat, if swallowed, which becomes key in the aspect of protecting the youngest. It is also worth noting that small elements of these devices are able to disrupt the diagnostic process medical after entering the body.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

Breakaway strength of the magnet in ideal conditions – what affects it?

Holding force of 480 kg is a theoretical maximum value conducted under standard conditions:

• on a plate made of structural steel, optimally conducting the magnetic flux
• whose thickness is min. 10 mm
• with a plane free of scratches
• with direct contact (no coatings)
• for force acting at a right angle (in the magnet axis)
• at room temperature

Key elements affecting lifting force

In real-world applications, the actual lifting capacity depends on many variables, listed from most significant:

• Gap between surfaces – even a fraction of a millimeter of separation (caused e.g. by veneer or dirt) diminishes the magnet efficiency, often by half at just 0.5 mm.
• Direction of force – highest force is available only during perpendicular pulling. The resistance to sliding of the magnet along the surface is typically many times lower (approx. 1/5 of the lifting capacity).
• Element thickness – for full efficiency, the steel must be adequately massive. Paper-thin metal limits the lifting capacity (the magnet "punches through" it).
• Material composition – different alloys attracts identically. High carbon content weaken the interaction with the magnet.
• Plate texture – ground elements guarantee perfect abutment, which improves field saturation. Uneven metal reduce efficiency.
• Temperature influence – hot environment reduces magnetic field. Exceeding the limit temperature can permanently damage the magnet.

* Holding force was tested on the plate surface of 20 mm thickness, when the force acted perpendicularly, however under attempts to slide the magnet the load capacity is reduced by as much as 75%. Additionally, even a minimal clearance {between} the magnet and the plate decreases the holding force.