AM lina fi 10 mm - magnetic accessories

Pros as well as cons of rare earth magnets.

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

• Their magnetic field is durable, and after around 10 years it drops only by ~1% (theoretically),
• They possess excellent resistance to weakening of magnetic properties due to external fields,
• A magnet with a metallic nickel surface looks better,
• Magnets possess impressive 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...
• Thanks to flexibility in designing and the ability to modify to unusual requirements,
• Wide application in innovative solutions – they find application in HDD drives, drive modules, diagnostic systems, as well as technologically advanced constructions.
• Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications

Disadvantages of NdFeB magnets:

• To avoid cracks upon strong impacts, we recommend using special steel housings. Such a solution secures the magnet and simultaneously increases its 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
• When exposed to humidity, magnets usually rust. For applications outside, it is recommended to use protective magnets, such as those in rubber or plastics, which prevent oxidation and corrosion.
• Limited possibility of producing threads in the magnet and complex forms - recommended is a housing - mounting mechanism.
• Health risk resulting from small fragments of magnets are risky, if swallowed, which becomes key in the aspect of protecting the youngest. Additionally, tiny parts of these magnets can disrupt the diagnostic process medical in case of swallowing.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

Maximum magnetic pulling force – what it depends on?

Holding force of 1592 kg is a theoretical maximum value performed under specific, ideal conditions:

• using a plate made of mild steel, functioning as a ideal flux conductor
• possessing a massiveness of minimum 10 mm to ensure full flux closure
• with a surface free of scratches
• without the slightest clearance between the magnet and steel
• under perpendicular force direction (90-degree angle)
• in temp. approx. 20°C

Practical lifting capacity: influencing factors

It is worth knowing that the working load may be lower influenced by the following factors, in order of importance:

• Gap between magnet and steel – even a fraction of a millimeter of distance (caused e.g. by veneer or dirt) diminishes the pulling force, often by half at just 0.5 mm.
• Force direction – note that the magnet holds strongest perpendicularly. Under shear forces, the holding force drops drastically, often to levels of 20-30% of the maximum value.
• Metal thickness – the thinner the sheet, the weaker the hold. Part of the magnetic field penetrates through instead of converting into lifting capacity.
• Plate material – mild steel gives the best results. Alloy steels reduce magnetic permeability and lifting capacity.
• Smoothness – ideal contact is obtained only on polished steel. Rough texture reduce the real contact area, weakening the magnet.
• Thermal factor – hot environment weakens pulling force. Too high temperature can permanently damage the magnet.

* Lifting capacity was measured by applying a steel plate with a smooth surface of optimal thickness (min. 20 mm), under vertically applied force, however under attempts to slide the magnet the load capacity is reduced by as much as 5 times. In addition, even a minimal clearance {between} the magnet and the plate lowers the load capacity.