AM ucho [M8] - magnetic accessories

Strengths and weaknesses of NdFeB magnets.

In addition to their long-term stability, neodymium magnets provide the following advantages:

• They have constant strength, and over more than 10 years their attraction force decreases symbolically – ~1% (according to theory),
• They are noted for resistance to demagnetization induced by presence of other magnetic fields,
• By applying a shiny coating of nickel, the element presents an proper look,
• Magnetic induction on the surface of the magnet remains extremely intense,
• Thanks to resistance to high temperature, they are capable of working (depending on the form) even at temperatures up to 230°C and higher...
• Thanks to the ability of accurate molding and adaptation to specialized requirements, NdFeB magnets can be produced in a variety of geometric configurations, which makes them more universal,
• Versatile presence in high-tech industry – they find application in hard drives, electric motors, advanced medical instruments, as well as complex engineering applications.
• Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications

Characteristics of disadvantages of neodymium magnets: application proposals

• To avoid cracks upon strong impacts, we recommend using special steel housings. Such a solution secures the magnet and simultaneously improves its durability.
• We warn that neodymium magnets can reduce their power at high temperatures. To prevent this, we suggest our specialized [AH] magnets, which work effectively even at 230°C.
• Magnets exposed to a humid environment can rust. Therefore while using outdoors, we recommend using waterproof magnets made of rubber, plastic or other material resistant to moisture
• Due to limitations in creating threads and complex forms in magnets, we recommend using a housing - magnetic mount.
• Health risk related to microscopic parts of magnets are risky, if swallowed, which gains importance in the context of child safety. Furthermore, small components of these products can be problematic in diagnostics medical after entering the body.
• High unit price – neodymium magnets are more expensive than other types of magnets (e.g. ferrite), which increases costs of application in large quantities

Maximum holding power of the magnet – what it depends on?

Information about lifting capacity is the result of a measurement for optimal configuration, assuming:

• with the application of a yoke made of special test steel, guaranteeing full magnetic saturation
• with a thickness of at least 10 mm
• characterized by even structure
• without the slightest air gap between the magnet and steel
• for force applied at a right angle (pull-off, not shear)
• at room temperature

Determinants of practical lifting force of a magnet

In practice, the actual lifting capacity is determined by several key aspects, listed from most significant:

• Distance (between the magnet and the plate), as even a very small distance (e.g. 0.5 mm) can cause a reduction in lifting capacity by up to 50% (this also applies to varnish, corrosion or dirt).
• Force direction – declared lifting capacity refers to detachment vertically. When slipping, the magnet exhibits significantly lower power (typically approx. 20-30% of maximum force).
• Element thickness – for full efficiency, the steel must be adequately massive. Paper-thin metal restricts the lifting capacity (the magnet "punches through" it).
• Metal type – different alloys attracts identically. Alloy additives worsen the attraction effect.
• Plate texture – smooth surfaces guarantee perfect abutment, which improves force. Uneven metal reduce efficiency.
• Operating temperature – neodymium magnets have a negative temperature coefficient. When it is hot they are weaker, and in frost they can be stronger (up to a certain limit).

* Lifting capacity testing was performed on plates with a smooth surface of optimal thickness, under perpendicular forces, in contrast under attempts to slide the magnet the holding force is lower. Additionally, even a slight gap {between} the magnet’s surface and the plate reduces the holding force.