AM lina fi 10 mm - magnetic accessories

Advantages as well as disadvantages of neodymium magnets NdFeB.

Besides their durability, neodymium magnets are valued for these benefits:

• They do not lose their even during nearly ten years – the reduction of lifting capacity is only ~1% (according to tests),
• They are highly resistant to demagnetization caused by external magnetic fields,
• In other words, due to the shiny nickel coating, the magnet obtains an professional appearance,
• They possess strong magnetic force measurable at the magnet’s surface,
• With the right combination of materials, they reach increased thermal stability, enabling operation at or above 230°C (depending on the structure),
• The ability for accurate shaping or adaptation to custom needs – neodymium magnets can be manufactured in multiple variants of geometries, which amplifies their functionality across industries,
• Important function in modern technologies – they are utilized in hard drives, rotating machines, medical equipment along with technologically developed systems,
• Thanks to their concentrated strength, small magnets offer high magnetic performance, with minimal size,

Disadvantages of neodymium magnets:

• They are fragile when subjected to a heavy impact. If the magnets are exposed to external force, we recommend in a protective case. The steel housing, in the form of a holder, protects the magnet from damage and additionally reinforces its overall durability,
• They lose field intensity at high temperatures. Most neodymium magnets experience permanent degradation in strength when heated above 80°C (depending on the form and height). However, we offer special variants with high temperature resistance that can operate up to 230°C or higher,
• They rust in a damp environment – during outdoor use, we recommend using sealed magnets, such as those made of non-metallic materials,
• Limited ability to create threads in the magnet – the use of a housing is recommended,
• Possible threat from tiny pieces may arise, especially if swallowed, which is notable in the health of young users. Additionally, minuscule fragments from these products may hinder health screening once in the system,
• Due to a complex production process, their cost is considerably higher,

Optimal lifting capacity of a neodymium magnet – what affects it?

The given strength of the magnet corresponds to the optimal strength, measured in ideal conditions, namely:

• with mild steel, used as a magnetic flux conductor
• with a thickness of minimum 10 mm
• with a smooth surface
• in conditions of no clearance
• under perpendicular detachment force
• in normal thermal conditions

Lifting capacity in real conditions – factors

Practical lifting force is determined by elements, by priority:

• Air gap between the magnet and the plate, because even a very small distance (e.g. 0.5 mm) causes a drop in lifting force of up to 50%.
• Direction of applied force, because the maximum lifting capacity is achieved under perpendicular application. The force required to slide the magnet along the plate is usually several times lower.
• Thickness of the plate, as a plate that is too thin causes part of the magnetic flux not to be used and to remain wasted in the air.
• Material of the plate, because higher carbon content lowers holding force, while higher iron content increases it. The best choice is steel with high magnetic permeability and high saturation induction.
• Surface of the plate, because the more smooth and polished it is, the better the contact and consequently the greater the magnetic saturation.
• Operating temperature, since all permanent magnets have a negative temperature coefficient. This means that at high temperatures they are weaker, while at sub-zero temperatures they become slightly stronger.

* Holding force was measured on the plate surface of 20 mm thickness, when a perpendicular force was applied, in contrast under parallel forces the holding force is lower. Moreover, even a small distance {between} the magnet and the plate lowers the holding force.