AM lina fi 10 mm - magnetic accessories

Advantages as well as disadvantages of neodymium magnets NdFeB.

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

• They do not lose their strength nearly ten years – the reduction of power is only ~1% (according to tests),
• They protect against demagnetization induced by ambient electromagnetic environments effectively,
• Thanks to the polished finish and silver coating, they have an aesthetic appearance,
• They exhibit extremely high levels of magnetic induction near the outer area of the magnet,
• These magnets tolerate elevated temperatures, often exceeding 230°C, when properly designed (in relation to form),
• The ability for custom shaping as well as adaptation to individual needs – neodymium magnets can be manufactured in a wide range of shapes and sizes, which amplifies their functionality across industries,
• Significant impact in cutting-edge sectors – they are used in computer drives, electromechanical systems, diagnostic apparatus along with high-tech tools,
• Relatively small size with high magnetic force – neodymium magnets offer intense magnetic field in small dimensions, which allows for use in miniature devices

Disadvantages of rare earth magnets:

• They can break when subjected to a strong impact. If the magnets are exposed to mechanical hits, we recommend in a steel housing. The steel housing, in the form of a holder, protects the magnet from breakage , and at the same time reinforces its overall strength,
• Magnets lose magnetic efficiency when exposed to temperatures exceeding 80°C. In most cases, this leads to irreversible performance loss (influenced by the magnet’s dimensions). To address this, we provide [AH] models with superior thermal resistance, able to operate even at 230°C or more,
• Magnets exposed to humidity can degrade. Therefore, for outdoor applications, we advise waterproof types made of coated materials,
• The use of a protective casing or external holder is recommended, since machining multi-axis shapes in neodymium magnets is restricted,
• Potential hazard from tiny pieces may arise, in case of ingestion, which is significant in the health of young users. Additionally, tiny components from these devices might complicate medical imaging if inside the body,
• Due to the price of neodymium, their cost is above average,

Maximum magnetic pulling force – what affects it?

The given strength of the magnet means the optimal strength, determined in the best circumstances, namely:

• with the use of low-carbon steel plate acting as a magnetic yoke
• with a thickness of minimum 10 mm
• with a polished side
• with zero air gap
• with vertical force applied
• in normal thermal conditions

Practical aspects of lifting capacity – factors

The lifting capacity of a magnet is determined by in practice key elements, from primary to secondary:

• Air gap between the magnet and the plate, since even a very small distance (e.g. 0.5 mm) can cause 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.

* Lifting capacity was determined by applying a smooth steel plate of suitable thickness (min. 20 mm), under perpendicular pulling force, whereas under parallel forces 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 holding force.