UMP 75x24 [M8+M10] GW F 200 kg - search holder

Advantages as well as disadvantages of NdFeB magnets.

Apart from their notable magnetism, neodymium magnets have these key benefits:

• Their strength remains stable, and after around 10 years it decreases only by ~1% (according to research),
• They show high resistance to demagnetization induced by external field influence,
• Thanks to the shiny finish, the layer of nickel, gold-plated, or silver gives an modern appearance,
• The surface of neodymium magnets generates a intense magnetic field – this is a distinguishing feature,
• Through (adequate) combination of ingredients, they can achieve high thermal resistance, enabling action at temperatures approaching 230°C and above...
• Thanks to freedom in constructing and the capacity to adapt to unusual requirements,
• Versatile presence in innovative solutions – they are commonly used in HDD drives, motor assemblies, diagnostic systems, and industrial machines.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

Disadvantages of NdFeB magnets:

• Brittleness is one of their disadvantages. Upon intense impact they can break. We recommend keeping them in a strong case, which not only protects them against impacts but also raises their 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 durability even at temperatures up to 230°C
• Magnets exposed to a humid environment can corrode. Therefore while using outdoors, we recommend using water-impermeable magnets made of rubber, plastic or other material protecting against moisture
• We recommend casing - magnetic mechanism, due to difficulties in creating nuts inside the magnet and complex shapes.
• Potential hazard resulting from small fragments of magnets are risky, in case of ingestion, which gains importance in the aspect of protecting the youngest. Furthermore, small elements of these magnets can disrupt the diagnostic process medical after entering the body.
• High unit price – neodymium magnets cost more than other types of magnets (e.g. ferrite), which can limit application in large quantities

Maximum lifting force for a neodymium magnet – what contributes to it?

Magnet power is the result of a measurement for ideal contact conditions, including:

• on a block made of mild steel, perfectly concentrating the magnetic flux
• whose transverse dimension is min. 10 mm
• with a plane cleaned and smooth
• with direct contact (no paint)
• under perpendicular force vector (90-degree angle)
• in temp. approx. 20°C

Lifting capacity in practice – influencing factors

Real force impacted by working environment parameters, including (from most important):

• Air gap (between the magnet and the metal), because even a very small clearance (e.g. 0.5 mm) can cause a drastic drop in lifting capacity by up to 50% (this also applies to varnish, rust or dirt).
• Loading method – catalog parameter refers to pulling vertically. When applying parallel force, the magnet exhibits significantly lower power (often approx. 20-30% of nominal force).
• Wall thickness – thin material does not allow full use of the magnet. Part of the magnetic field passes through the material instead of generating force.
• Plate material – mild steel gives the best results. Alloy steels decrease magnetic permeability and lifting capacity.
• Surface condition – smooth surfaces guarantee perfect abutment, which improves force. Rough surfaces reduce efficiency.
• Temperature – heating the magnet results in weakening of force. It is worth remembering the maximum operating temperature for a given model.

* Lifting capacity testing was carried out on plates with a smooth surface of suitable thickness, under perpendicular forces, however under shearing force the holding force is lower. In addition, even a small distance {between} the magnet and the plate lowers the holding force.