SM 18x200 [2xM5] / N42 - magnetic separator

Strengths as well as weaknesses of NdFeB magnets.

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

• Their strength remains stable, and after around ten years it decreases only by ~1% (theoretically),
• They maintain their magnetic properties even under external field action,
• In other words, due to the reflective layer of silver, the element gains visual value,
• The surface of neodymium magnets generates a strong magnetic field – this is a key feature,
• Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their form) at temperatures up to 230°C and above...
• Possibility of exact forming and modifying to precise applications,
• Huge importance in modern industrial fields – they serve a role in magnetic memories, brushless drives, medical equipment, and technologically advanced constructions.
• Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in small dimensions, which allows their use in miniature devices

Disadvantages of NdFeB magnets:

• Susceptibility to cracking is one of their disadvantages. Upon intense impact they can fracture. We advise keeping them in a strong case, which not only secures them against impacts but also increases their durability
• We warn that neodymium magnets can lose their power at high temperatures. To prevent this, we recommend our specialized [AH] magnets, which work effectively even at 230°C.
• Magnets exposed to a humid environment can rust. Therefore during using outdoors, we advise using waterproof magnets made of rubber, plastic or other material resistant to moisture
• Due to limitations in realizing threads and complex forms in magnets, we recommend using cover - magnetic mechanism.
• Possible danger resulting from small fragments of magnets pose a threat, if swallowed, which is particularly important in the aspect of protecting the youngest. Additionally, small components of these products can complicate diagnosis medical when they are in the body.
• With mass production the cost of neodymium magnets can be a barrier,

Optimal lifting capacity of a neodymium magnet – what contributes to it?

Information about lifting capacity was determined for the most favorable conditions, taking into account:

• using a plate made of high-permeability steel, acting as a circuit closing element
• whose thickness is min. 10 mm
• with a surface cleaned and smooth
• without any insulating layer between the magnet and steel
• for force applied at a right angle (in the magnet axis)
• at standard ambient temperature

Lifting capacity in practice – influencing factors

In real-world applications, the actual holding force depends on several key aspects, ranked from crucial:

• Space between magnet and steel – even a fraction of a millimeter of separation (caused e.g. by varnish or dirt) significantly weakens the pulling force, often by half at just 0.5 mm.
• Force direction – declared lifting capacity refers to detachment vertically. When attempting to slide, the magnet holds much less (typically approx. 20-30% of maximum force).
• Wall thickness – the thinner the sheet, the weaker the hold. Magnetic flux passes through the material instead of converting into lifting capacity.
• Metal type – different alloys attracts identically. Alloy additives weaken the interaction with the magnet.
• Surface structure – the smoother and more polished the plate, the better the adhesion and stronger the hold. Roughness creates an air distance.
• Heat – NdFeB sinters have a negative temperature coefficient. When it is hot they lose power, and at low temperatures gain strength (up to a certain limit).

* Holding force was measured on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, in contrast under attempts to slide the magnet the holding force is lower. Additionally, even a small distance {between} the magnet’s surface and the plate decreases the load capacity.

Optimal lifting capacity of a neodymium magnet – what contributes to it?

Information about lifting capacity was determined for the most favorable conditions, taking into account:

• using a plate made of high-permeability steel, acting as a circuit closing element
• whose thickness is min. 10 mm
• with a surface cleaned and smooth
• without any insulating layer between the magnet and steel
• for force applied at a right angle (in the magnet axis)
• at standard ambient temperature

Lifting capacity in practice – influencing factors

In real-world applications, the actual holding force depends on several key aspects, ranked from crucial:

• Space between magnet and steel – even a fraction of a millimeter of separation (caused e.g. by varnish or dirt) significantly weakens the pulling force, often by half at just 0.5 mm.
• Force direction – declared lifting capacity refers to detachment vertically. When attempting to slide, the magnet holds much less (typically approx. 20-30% of maximum force).
• Wall thickness – the thinner the sheet, the weaker the hold. Magnetic flux passes through the material instead of converting into lifting capacity.
• Metal type – different alloys attracts identically. Alloy additives weaken the interaction with the magnet.
• Surface structure – the smoother and more polished the plate, the better the adhesion and stronger the hold. Roughness creates an air distance.
• Heat – NdFeB sinters have a negative temperature coefficient. When it is hot they lose power, and at low temperatures gain strength (up to a certain limit).

* Holding force was measured on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, in contrast under attempts to slide the magnet the holding force is lower. Additionally, even a small distance {between} the magnet’s surface and the plate decreases the load capacity.