AM ucho [M8] - magnetic accessories

Strengths as well as weaknesses of rare earth magnets.

Apart from their consistent holding force, neodymium magnets have these key benefits:

• They retain attractive force for nearly 10 years – the drop is just ~1% (according to analyses),
• They have excellent resistance to magnetic field loss as a result of external magnetic sources,
• A magnet with a smooth silver surface has better aesthetics,
• Magnets exhibit excellent magnetic induction on the surface,
• 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 ability of flexible shaping and adaptation to individualized needs, magnetic components can be manufactured in a broad palette of shapes and sizes, which increases their versatility,
• Significant place in modern technologies – they are used in magnetic memories, electric motors, precision medical tools, and multitasking production systems.
• Relatively small size with high pulling force – neodymium magnets offer high power in compact dimensions, which allows their use in small systems

Characteristics of disadvantages of neodymium magnets and proposals for their use:

• At very strong impacts they can break, therefore we advise placing them in strong housings. A metal housing provides additional protection against damage, as well as increases the magnet's durability.
• Neodymium magnets decrease their strength 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 stability even at temperatures up to 230°C
• They rust in a humid environment. For use outdoors we recommend using waterproof magnets e.g. in rubber, plastic
• We recommend a housing - magnetic mechanism, due to difficulties in creating nuts inside the magnet and complex shapes.
• Health risk to health – tiny shards of magnets are risky, in case of ingestion, which becomes key in the aspect of protecting the youngest. Furthermore, small components of these magnets can disrupt the diagnostic process medical in case of swallowing.
• With mass production the cost of neodymium magnets is a challenge,

Maximum lifting capacity of the magnet – what contributes to it?

Magnet power was defined for optimal configuration, including:

• with the use of a sheet made of special test steel, ensuring full magnetic saturation
• possessing a massiveness of at least 10 mm to avoid saturation
• characterized by smoothness
• with direct contact (without impurities)
• during pulling in a direction perpendicular to the mounting surface
• at temperature room level

Determinants of lifting force in real conditions

During everyday use, the real power is determined by several key aspects, ranked from the most important:

• Clearance – the presence of any layer (rust, tape, air) acts as an insulator, which reduces power steeply (even by 50% at 0.5 mm).
• Pull-off angle – remember that the magnet holds strongest perpendicularly. Under shear forces, the capacity drops significantly, often to levels of 20-30% of the maximum value.
• Substrate thickness – for full efficiency, the steel must be sufficiently thick. Thin sheet restricts the lifting capacity (the magnet "punches through" it).
• Steel grade – the best choice is pure iron steel. Stainless steels may generate lower lifting capacity.
• Surface condition – smooth surfaces guarantee perfect abutment, which improves field saturation. Rough surfaces weaken the grip.
• Temperature influence – hot environment reduces pulling force. Exceeding the limit temperature can permanently demagnetize the magnet.

* Lifting capacity was assessed by applying a smooth steel plate of optimal thickness (min. 20 mm), under perpendicular pulling force, however under parallel forces the holding force is lower. Additionally, even a small distance {between} the magnet and the plate lowers the load capacity.