UMGZ 36x18x8 [M6] GZ / N38 - magnetic holder external thread

Advantages and disadvantages of neodymium magnets NdFeB.

Apart from their strong power, neodymium magnets have these key benefits:

• They retain their full power for almost ten years – the loss is just ~1% (according to analyses),
• They remain magnetized despite exposure to magnetic surroundings,
• In other words, due to the shiny nickel coating, the magnet obtains an stylish appearance,
• 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 profile),
• Thanks to the possibility in shaping and the capability to adapt to specific requirements, neodymium magnets can be created in various configurations, which expands their application range,
• Significant impact in cutting-edge sectors – they are utilized in HDDs, rotating machines, healthcare devices along with other advanced devices,
• Compactness – despite their small size, they deliver powerful magnetism, making them ideal for precision applications

Disadvantages of rare earth magnets:

• They can break when subjected to a sudden impact. If the magnets are exposed to external force, it is advisable to use in a protective enclosure. The steel housing, in the form of a holder, protects the magnet from breakage , and at the same time reinforces its overall durability,
• Magnets lose power when exposed to temperatures exceeding 80°C. In most cases, this leads to irreversible field weakening (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, it's best to use waterproof types made of plastic,
• Limited ability to create precision features in the magnet – the use of a magnetic holder is recommended,
• Potential hazard related to magnet particles may arise, when consumed by mistake, which is significant in the protection of children. Moreover, tiny components from these assemblies have the potential to hinder health screening once in the system,
• Due to expensive raw materials, their cost is considerably higher,

Maximum holding power of the magnet – what contributes to it?

The given pulling force of the magnet corresponds to the maximum force, determined in a perfect environment, that is:

• using a steel plate with low carbon content, acting as a magnetic circuit closure
• of a thickness of at least 10 mm
• with a smooth surface
• in conditions of no clearance
• under perpendicular detachment force
• under standard ambient temperature

Key elements affecting lifting force

The lifting capacity of a magnet is influenced by in practice the following factors, according to their importance:

• 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 testing was carried out on a smooth plate of suitable thickness, under perpendicular forces, whereas under attempts to slide the magnet the lifting capacity is smaller. In addition, even a slight gap {between} the magnet and the plate lowers the holding force.