SM 32x150 [2xM8] / N42 - magnetic separator

Strengths as well as weaknesses of NdFeB magnets.

In addition to their magnetic efficiency, neodymium magnets provide the following advantages:

• They have constant strength, and over more than ten years their attraction force decreases symbolically – ~1% (in testing),
• Magnets very well defend themselves against demagnetization caused by foreign field sources,
• By covering with a reflective layer of gold, the element presents an professional look,
• Magnets are distinguished by excellent magnetic induction on the surface,
• Due to their durability and thermal resistance, neodymium magnets are capable of operate (depending on the form) even at high temperatures reaching 230°C or more...
• Thanks to the possibility of flexible molding and adaptation to individualized solutions, NdFeB magnets can be produced in a wide range of geometric configurations, which amplifies use scope,
• Versatile presence in electronics industry – they find application in magnetic memories, electromotive mechanisms, medical equipment, and industrial machines.
• Relatively small size with high pulling force – neodymium magnets offer high power in small dimensions, which makes them useful in miniature devices

What to avoid - cons of neodymium magnets: tips and applications.

• At strong impacts they can crack, therefore we advise placing them in steel cases. A metal housing provides additional protection against damage, as well as increases the magnet's durability.
• We warn that neodymium magnets can reduce their strength at high temperatures. To prevent this, we recommend our specialized [AH] magnets, which work effectively even at 230°C.
• They rust 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 realizing threads inside the magnet and complicated forms.
• Possible danger related to microscopic parts of magnets can be dangerous, in case of ingestion, which gains importance in the aspect of protecting the youngest. Furthermore, tiny parts of these products can disrupt the diagnostic process medical after entering the body.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

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

Holding force of 0 kg is a theoretical maximum value conducted under standard conditions:

• with the contact of a sheet made of special test steel, guaranteeing maximum field concentration
• possessing a massiveness of at least 10 mm to avoid saturation
• characterized by lack of roughness
• with zero gap (no coatings)
• under axial force vector (90-degree angle)
• at standard ambient temperature

Lifting capacity in real conditions – factors

Real force is influenced by working environment parameters, such as (from priority):

• Space between magnet and steel – every millimeter of distance (caused e.g. by veneer or dirt) significantly weakens the pulling force, often by half at just 0.5 mm.
• Force direction – remember that the magnet has greatest strength perpendicularly. Under shear forces, the holding force drops drastically, often to levels of 20-30% of the maximum value.
• Element thickness – for full efficiency, the steel must be adequately massive. Paper-thin metal restricts the lifting capacity (the magnet "punches through" it).
• Material type – ideal substrate is high-permeability steel. Cast iron may generate lower lifting capacity.
• Surface finish – full contact is obtained only on smooth steel. Any scratches and bumps create air cushions, reducing force.
• Temperature – temperature increase causes a temporary drop of induction. It is worth remembering the maximum operating temperature for a given model.

* Holding force was tested on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, however under attempts to slide the magnet the load capacity is reduced by as much as 75%. Additionally, even a small distance {between} the magnet’s surface and the plate lowers the lifting capacity.