SM 32x325 [2xM8] / N52 - magnetic separator

Strengths as well as weaknesses of NdFeB magnets.

Besides their high retention, neodymium magnets are valued for these benefits:

• Their power is durable, and after around ten years it drops only by ~1% (according to research),
• They possess excellent resistance to magnetism drop due to opposing magnetic fields,
• Thanks to the glossy finish, the surface of Ni-Cu-Ni, gold-plated, or silver gives an professional appearance,
• Magnetic induction on the working part of the magnet turns out to be extremely intense,
• Neodymium magnets are characterized by very high magnetic induction on the magnet surface and are able to act (depending on the shape) even at a temperature of 230°C or more...
• Thanks to modularity in forming and the capacity to customize to individual projects,
• Universal use in future technologies – they are commonly used in mass storage devices, drive modules, advanced medical instruments, and other advanced devices.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in compact dimensions, which allows their use in small systems

Disadvantages of NdFeB magnets:

• To avoid cracks upon strong impacts, we recommend using special steel housings. Such a solution protects the magnet and simultaneously increases its durability.
• When exposed to high temperature, neodymium magnets suffer a drop in strength. Often, when the temperature exceeds 80°C, their power decreases (depending on the size and shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
• They oxidize in a humid environment. For use outdoors we recommend using waterproof magnets e.g. in rubber, plastic
• We suggest cover - magnetic mount, due to difficulties in creating nuts inside the magnet and complicated shapes.
• Potential hazard resulting from small fragments of magnets can be dangerous, in case of ingestion, which gains importance in the context of child safety. It is also worth noting that tiny parts of these products can be problematic in diagnostics medical when they are in the body.
• Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Maximum lifting capacity of the magnet – what affects it?

The declared magnet strength represents the maximum value, measured under ideal test conditions, specifically:

• with the contact of a sheet made of low-carbon steel, guaranteeing full magnetic saturation
• whose thickness is min. 10 mm
• with a surface cleaned and smooth
• under conditions of ideal adhesion (surface-to-surface)
• during detachment in a direction vertical to the plane
• in temp. approx. 20°C

Impact of factors on magnetic holding capacity in practice

Please note that the working load will differ subject to the following factors, starting with the most relevant:

• Distance – the presence of foreign body (rust, dirt, air) acts as an insulator, which lowers power steeply (even by 50% at 0.5 mm).
• Force direction – note that the magnet holds strongest perpendicularly. Under sliding down, the holding force drops significantly, often to levels of 20-30% of the maximum value.
• 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.
• Metal type – different alloys attracts identically. High carbon content weaken the interaction with the magnet.
• Surface condition – smooth surfaces guarantee perfect abutment, which increases field saturation. Uneven metal reduce efficiency.
• Temperature influence – high temperature reduces pulling force. Exceeding the limit temperature can permanently damage the magnet.

* Lifting capacity testing was conducted on a smooth plate of suitable thickness, under perpendicular forces, in contrast under parallel forces the load capacity is reduced by as much as fivefold. Additionally, even a slight gap {between} the magnet’s surface and the plate reduces the lifting capacity.