AM ucho [M8] - magnetic accessories

Advantages and disadvantages of NdFeB magnets.

In addition to their magnetic capacity, neodymium magnets provide the following advantages:

• They do not lose power, even over nearly 10 years – the reduction in power is only ~1% (based on measurements),
• They possess excellent resistance to magnetic field loss due to external magnetic sources,
• By applying a reflective layer of silver, the element gains an aesthetic look,
• Neodymium magnets ensure maximum magnetic induction on a their surface, which allows for strong attraction,
• Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their form) at temperatures up to 230°C and above...
• Due to the potential of flexible molding and customization to unique solutions, neodymium magnets can be modeled in a variety of forms and dimensions, which makes them more universal,
• Versatile presence in innovative solutions – they are commonly used in mass storage devices, electric motors, medical devices, and other advanced devices.
• Thanks to their power density, small magnets offer high operating force, occupying minimum space,

Disadvantages of NdFeB magnets:

• They are fragile upon heavy impacts. To avoid cracks, it is worth protecting magnets in a protective case. Such protection not only shields the magnet but also increases its resistance to damage
• We warn that neodymium magnets can reduce their strength at high temperatures. To prevent this, we recommend our specialized [AH] magnets, which work effectively even at 230°C.
• They oxidize in a humid environment. For use outdoors we advise using waterproof magnets e.g. in rubber, plastic
• Limited possibility of producing nuts in the magnet and complex shapes - preferred is cover - mounting mechanism.
• Potential hazard resulting from small fragments of magnets can be dangerous, in case of ingestion, which becomes key in the context of child safety. Furthermore, small components of these magnets can complicate diagnosis medical in case of swallowing.
• High unit price – neodymium magnets have a higher price than other types of magnets (e.g. ferrite), which can limit application in large quantities

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

Magnet power was defined for the most favorable conditions, taking into account:

• on a base made of structural steel, effectively closing the magnetic field
• possessing a massiveness of minimum 10 mm to ensure full flux closure
• with a plane free of scratches
• without any clearance between the magnet and steel
• for force acting at a right angle (in the magnet axis)
• at ambient temperature room level

Magnet lifting force in use – key factors

In real-world applications, the actual holding force is determined by many variables, listed from most significant:

• Space between magnet and steel – every millimeter of separation (caused e.g. by veneer or dirt) diminishes the pulling force, often by half at just 0.5 mm.
• Direction of force – maximum parameter is obtained only during pulling at a 90° angle. The shear force of the magnet along the surface is typically several times smaller (approx. 1/5 of the lifting capacity).
• Steel thickness – too thin steel does not close the flux, causing part of the flux to be escaped into the air.
• Plate material – mild steel gives the best results. Alloy admixtures reduce magnetic permeability and holding force.
• Plate texture – smooth surfaces guarantee perfect abutment, which improves field saturation. Uneven metal weaken the grip.
• Temperature – temperature increase causes a temporary drop of force. It is worth remembering the maximum operating temperature for a given model.

* Holding force was checked on the plate surface of 20 mm thickness, when the force acted perpendicularly, however under shearing force the load capacity is reduced by as much as 5 times. In addition, even a slight gap {between} the magnet and the plate reduces the holding force.