KM HF - 11,3 kg - magnetic bracket

Advantages and disadvantages of neodymium magnets NdFeB.

In addition to their pulling strength, neodymium magnets provide the following advantages:

• They virtually do not lose power, because even after 10 years, the performance loss is only ~1% (in laboratory conditions),
• They show exceptional resistance to demagnetization from external field exposure,
• Because of the brilliant layer of silver, the component looks high-end,
• The outer field strength of the magnet shows elevated magnetic properties,
• These magnets tolerate extreme temperatures, often exceeding 230°C, when properly designed (in relation to form),
• Thanks to the flexibility in shaping and the capability to adapt to individual requirements, neodymium magnets can be created in various configurations, which broadens their usage potential,
• Important function in new technology industries – they serve a purpose in computer drives, electric drives, clinical machines and other advanced devices,
• Compactness – despite their small size, they generate strong force, making them ideal for precision applications

Disadvantages of magnetic elements:

• They may fracture when subjected to a heavy impact. If the magnets are exposed to external force, they should be placed in a metal holder. The steel housing, in the form of a holder, protects the magnet from damage and increases its overall durability,
• Magnets lose pulling force when exposed to temperatures exceeding 80°C. In most cases, this leads to irreversible power drop (influenced by the magnet’s structure). To address this, we provide [AH] models with superior thermal resistance, able to operate even at 230°C or more,
• Due to corrosion risk in humid conditions, it is recommended to use sealed magnets made of protective material for outdoor use,
• Limited ability to create precision features in the magnet – the use of a external casing is recommended,
• Potential hazard from tiny pieces may arise, if ingested accidentally, which is notable in the family environments. Furthermore, minuscule fragments from these magnets might complicate medical imaging after being swallowed,
• In cases of mass production, neodymium magnet cost may not be economically viable,

Breakaway strength of the magnet in ideal conditions – what contributes to it?

The given lifting capacity of the magnet means the maximum lifting force, calculated in the best circumstances, specifically:

• using a steel plate with low carbon content, serving as a magnetic circuit closure
• having a thickness of no less than 10 millimeters
• with a smooth surface
• with no separation
• with vertical force applied
• in normal thermal conditions

Determinants of lifting force in real conditions

Practical lifting force is determined by factors, listed from the most critical to the less significant:

• Air gap between the magnet and the plate, since 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.

* Lifting capacity was determined with the use of a smooth steel plate of suitable thickness (min. 20 mm), under vertically applied force, whereas under attempts to slide the magnet the lifting capacity is smaller. In addition, even a minimal clearance {between} the magnet and the plate lowers the load capacity.