AM lina fi 10 mm - magnetic accessories

Strengths and weaknesses of rare earth magnets.

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

• They have stable power, and over nearly 10 years their performance decreases symbolically – ~1% (in testing),
• They show high resistance to demagnetization induced by external disturbances,
• Thanks to the smooth finish, the surface of nickel, gold-plated, or silver gives an aesthetic appearance,
• The surface of neodymium magnets generates a unique magnetic field – this is a distinguishing feature,
• Thanks to resistance to high temperature, they are capable of working (depending on the shape) even at temperatures up to 230°C and higher...
• Thanks to the option of accurate shaping and customization to unique projects, neodymium magnets can be produced in a wide range of forms and dimensions, which increases their versatility,
• Fundamental importance in advanced technology sectors – they are utilized in hard drives, motor assemblies, medical equipment, also other advanced devices.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in small dimensions, which allows their use in small systems

Characteristics of disadvantages of neodymium magnets: application proposals

• At strong impacts they can crack, therefore we recommend placing them in special holders. A metal housing provides additional protection against damage and increases the magnet's durability.
• When exposed to high temperature, neodymium magnets suffer a drop in strength. Often, when the temperature exceeds 80°C, their strength 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
• They rust in a humid environment - during use outdoors we suggest using waterproof magnets e.g. in rubber, plastic
• Limited ability of making threads in the magnet and complicated forms - preferred is a housing - mounting mechanism.
• Possible danger to health – tiny shards of magnets pose a threat, when accidentally swallowed, which becomes key in the context of child health protection. Additionally, tiny parts of these devices can complicate diagnosis medical when they are in the body.
• High unit price – neodymium magnets are more expensive than other types of magnets (e.g. ferrite), which hinders application in large quantities

Optimal lifting capacity of a neodymium magnet – what contributes to it?

Information about lifting capacity was defined for ideal contact conditions, including:

• with the application of a sheet made of low-carbon steel, ensuring full magnetic saturation
• whose transverse dimension reaches at least 10 mm
• with a surface perfectly flat
• without any insulating layer between the magnet and steel
• under vertical force vector (90-degree angle)
• in temp. approx. 20°C

Lifting capacity in real conditions – factors

Holding efficiency is influenced by specific conditions, including (from most important):

• Clearance – existence of any layer (rust, dirt, air) acts as an insulator, which reduces power steeply (even by 50% at 0.5 mm).
• Load vector – highest force is obtained only during perpendicular pulling. The resistance to sliding of the magnet along the plate is standardly many times smaller (approx. 1/5 of the lifting capacity).
• Element thickness – for full efficiency, the steel must be adequately massive. Thin sheet limits the attraction force (the magnet "punches through" it).
• Material type – ideal substrate is high-permeability steel. Stainless steels may attract less.
• Surface quality – the smoother and more polished the plate, the larger the contact zone and higher the lifting capacity. Roughness creates an air distance.
• Heat – neodymium magnets have a sensitivity to temperature. When it is hot they are weaker, and in frost they can be stronger (up to a certain limit).

* Lifting capacity was determined by applying a smooth steel plate of suitable thickness (min. 20 mm), under perpendicular pulling force, in contrast under shearing force the load capacity is reduced by as much as 5 times. Moreover, even a slight gap {between} the magnet’s surface and the plate lowers the holding force.