AM ucho [M8] - magnetic accessories

Strengths and weaknesses of rare earth magnets.

Besides their magnetic performance, neodymium magnets are valued for these benefits:

• They have stable power, and over more than ten years their attraction force decreases symbolically – ~1% (in testing),
• They have excellent resistance to magnetic field loss due to opposing magnetic fields,
• In other words, due to the aesthetic finish of silver, the element is aesthetically pleasing,
• The surface of neodymium magnets generates a powerful magnetic field – this is a key feature,
• Due to their durability and thermal resistance, neodymium magnets can operate (depending on the shape) even at high temperatures reaching 230°C or more...
• In view of the potential of precise molding and adaptation to specialized requirements, magnetic components can be produced in a broad palette of shapes and sizes, which increases their versatility,
• Fundamental importance in electronics industry – they are utilized in computer drives, motor assemblies, medical devices, and multitasking production systems.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in small dimensions, which enables their usage in miniature devices

What to avoid - cons of neodymium magnets: tips and applications.

• They are prone to damage upon heavy impacts. To avoid cracks, it is worth securing magnets in special housings. Such protection not only shields the magnet but also increases its resistance to damage
• Neodymium magnets lose their force under the influence of heating. As soon as 80°C is exceeded, many of them start losing their force. Therefore, we recommend our special magnets marked [AH], which maintain durability even at temperatures 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 stable to moisture, when using outdoors
• Due to limitations in creating nuts and complex forms in magnets, we recommend using casing - magnetic holder.
• Health risk resulting from small fragments of magnets can be dangerous, if swallowed, which gains importance in the aspect of protecting the youngest. Furthermore, small components of these magnets are able to be problematic in diagnostics medical when they are in the body.
• With budget limitations the cost of neodymium magnets can be a barrier,

Maximum holding power of the magnet – what affects it?

The declared magnet strength refers to the peak performance, measured under optimal environment, specifically:

• using a sheet made of high-permeability steel, acting as a ideal flux conductor
• whose thickness reaches at least 10 mm
• with an polished contact surface
• with total lack of distance (no coatings)
• under perpendicular force vector (90-degree angle)
• at room temperature

Impact of factors on magnetic holding capacity in practice

Holding efficiency impacted by specific conditions, mainly (from most important):

• Clearance – existence of any layer (rust, tape, gap) interrupts the magnetic circuit, which reduces capacity steeply (even by 50% at 0.5 mm).
• Angle of force application – maximum parameter is reached only during perpendicular pulling. The resistance to sliding of the magnet along the surface is standardly many times lower (approx. 1/5 of the lifting capacity).
• Wall thickness – thin material does not allow full use of the magnet. Magnetic flux passes through the material instead of converting into lifting capacity.
• Steel type – low-carbon steel attracts best. Higher carbon content reduce magnetic properties and lifting capacity.
• Surface quality – the smoother and more polished the surface, the larger the contact zone and stronger the hold. Roughness acts like micro-gaps.
• Temperature – heating the magnet causes a temporary drop of induction. Check the maximum operating temperature for a given model.

* Holding force was checked on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, however under shearing force the holding force is lower. Moreover, even a slight gap {between} the magnet’s surface and the plate lowers the holding force.