SM 32x100 [2xM8] / N52 - magnetic separator

Strengths and weaknesses of NdFeB magnets.

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

• They have constant strength, and over around ten years their performance decreases symbolically – ~1% (according to theory),
• They possess excellent resistance to magnetic field loss due to external magnetic sources,
• Thanks to the shimmering finish, the layer of Ni-Cu-Ni, gold, or silver gives an elegant appearance,
• Neodymium magnets achieve maximum magnetic induction on a their surface, which ensures high operational effectiveness,
• Through (adequate) combination of ingredients, they can achieve high thermal strength, allowing for action at temperatures approaching 230°C and above...
• Possibility of detailed shaping as well as adjusting to individual needs,
• Significant place in future technologies – they find application in mass storage devices, motor assemblies, advanced medical instruments, as well as modern systems.
• Thanks to efficiency per cm³, small magnets offer high operating force, occupying minimum space,

Drawbacks and weaknesses of neodymium magnets: tips and applications.

• Susceptibility to cracking is one of their disadvantages. Upon strong impact they can fracture. We recommend keeping them in a steel housing, which not only protects them against impacts but also increases their durability
• When exposed to high temperature, neodymium magnets suffer a drop in force. Often, when the temperature exceeds 80°C, their strength decreases (depending on the size, as well as 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 suggest using waterproof magnets e.g. in rubber, plastic
• Due to limitations in creating nuts and complex forms in magnets, we propose using cover - magnetic mechanism.
• Possible danger resulting from small fragments of magnets are risky, in case of ingestion, which gains importance in the aspect of protecting the youngest. Additionally, tiny parts of these products are able to be problematic in diagnostics medical when they are in the body.
• Due to complex production process, their price is higher than average,

Detachment force of the magnet in optimal conditions – what contributes to it?

The lifting capacity listed is a theoretical maximum value performed under the following configuration:

• on a plate made of mild steel, perfectly concentrating the magnetic field
• possessing a thickness of minimum 10 mm to ensure full flux closure
• with an polished touching surface
• with total lack of distance (no paint)
• under perpendicular force direction (90-degree angle)
• at ambient temperature approx. 20 degrees Celsius

Practical lifting capacity: influencing factors

In real-world applications, the actual lifting capacity results from many variables, listed from crucial:

• Air gap (between the magnet and the metal), as even a very small clearance (e.g. 0.5 mm) results in a reduction in force by up to 50% (this also applies to varnish, rust or debris).
• Force direction – catalog parameter refers to detachment vertically. When attempting to slide, the magnet exhibits much less (typically approx. 20-30% of maximum force).
• Element thickness – for full efficiency, the steel must be adequately massive. Paper-thin metal limits the lifting capacity (the magnet "punches through" it).
• Metal type – not every steel reacts the same. Alloy additives worsen the interaction with the magnet.
• Surface structure – the more even the surface, the better the adhesion and stronger the hold. Roughness acts like micro-gaps.
• Temperature – heating the magnet causes a temporary drop of force. It is worth remembering the maximum operating temperature for a given model.

* Lifting capacity testing was performed on plates with a smooth surface of optimal thickness, under a perpendicular pulling force, in contrast under parallel forces the lifting capacity is smaller. Additionally, even a slight gap {between} the magnet and the plate reduces the load capacity.