AM ucho [M8] - magnetic accessories

Pros as well as cons of neodymium magnets.

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

• Their magnetic field is durable, and after around ten years it decreases only by ~1% (according to research),
• They possess excellent resistance to magnetism drop due to opposing magnetic fields,
• By applying a shiny coating of gold, the element gains an proper look,
• Magnetic induction on the surface of the magnet turns out to be strong,
• Through (adequate) combination of ingredients, they can achieve high thermal strength, allowing for functioning at temperatures approaching 230°C and above...
• Due to the option of flexible forming and adaptation to unique requirements, NdFeB magnets can be manufactured in a wide range of forms and dimensions, which makes them more universal,
• Versatile presence in advanced technology sectors – they serve a role in magnetic memories, electric motors, precision medical tools, as well as complex engineering applications.
• Thanks to efficiency per cm³, 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 special housings. Such protection not only protects the magnet but also increases its resistance to damage
• When exposed to high temperature, neodymium magnets suffer a drop in force. 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 advise using waterproof magnets made of rubber, plastic or other material resistant to moisture, when using outdoors
• Limited ability of producing threads in the magnet and complicated shapes - recommended is casing - mounting mechanism.
• Potential hazard related to microscopic parts of magnets are risky, when accidentally swallowed, which gains importance in the context of child safety. Furthermore, small elements of these magnets can disrupt the diagnostic process medical after entering the body.
• Due to neodymium price, their price exceeds standard values,

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

Breakaway force was defined for optimal configuration, assuming:

• using a plate made of high-permeability steel, acting as a ideal flux conductor
• whose transverse dimension equals approx. 10 mm
• with a plane cleaned and smooth
• without the slightest air gap between the magnet and steel
• for force acting at a right angle (in the magnet axis)
• at ambient temperature room level

Lifting capacity in real conditions – factors

Real force is influenced by specific conditions, mainly (from priority):

• Gap (between the magnet and the plate), as even a very small clearance (e.g. 0.5 mm) results in a reduction in force by up to 50% (this also applies to varnish, rust or debris).
• Load vector – highest force is reached only during pulling at a 90° angle. The force required to slide of the magnet along the surface is standardly several times lower (approx. 1/5 of the lifting capacity).
• Steel thickness – insufficiently thick steel causes magnetic saturation, causing part of the power to be lost into the air.
• Material composition – different alloys reacts the same. High carbon content weaken the attraction effect.
• Smoothness – ideal contact is obtained only on polished steel. Any scratches and bumps reduce the real contact area, weakening the magnet.
• Heat – neodymium magnets have a sensitivity to temperature. When it is hot they lose power, and in frost they can be stronger (up to a certain limit).

* Lifting capacity testing was carried out on plates with a smooth surface of optimal thickness, under perpendicular forces, in contrast under attempts to slide the magnet the load capacity is reduced by as much as 5 times. Additionally, even a minimal clearance {between} the magnet’s surface and the plate decreases the load capacity.