SM 25x125 [2xM8] / N52 - magnetic separator

Advantages as well as disadvantages of neodymium magnets.

Besides their magnetic performance, neodymium magnets are valued for these benefits:

• They virtually do not lose strength, because even after 10 years the decline in efficiency is only ~1% (based on calculations),
• Neodymium magnets are characterized by remarkably resistant to demagnetization caused by magnetic disturbances,
• The use of an metallic finish of noble metals (nickel, gold, silver) causes the element to be more visually attractive,
• Magnets possess extremely high magnetic induction on the active area,
• Neodymium magnets are characterized by extremely 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 flexibility in shaping and the ability to modify to specific needs,
• Wide application in high-tech industry – they find application in data components, electromotive mechanisms, diagnostic systems, as well as other advanced devices.
• Compactness – despite small sizes they provide effective action, making them ideal for precision applications

Disadvantages of neodymium magnets:

• To avoid cracks under impact, we recommend using special steel housings. Such a solution secures the magnet and simultaneously improves its durability.
• Neodymium magnets decrease their strength under the influence of heating. As soon as 80°C is exceeded, many of them start losing their force. Therefore, we recommend our special magnets marked [AH], which maintain durability even at temperatures up to 230°C
• They rust in a humid environment. For use outdoors we advise using waterproof magnets e.g. in rubber, plastic
• Due to limitations in producing nuts and complex shapes in magnets, we recommend using cover - magnetic mount.
• Possible danger to health – tiny shards of magnets pose a threat, if swallowed, which becomes key in the context of child safety. It is also worth noting that small components of these devices are able to be problematic in diagnostics medical after entering the body.
• With mass production the cost of neodymium magnets can be a barrier,

Breakaway strength of the magnet in ideal conditions – what affects it?

Information about lifting capacity was determined for optimal configuration, including:

• with the contact of a yoke made of special test steel, ensuring maximum field concentration
• whose transverse dimension equals approx. 10 mm
• with an ground contact surface
• with total lack of distance (no coatings)
• during detachment in a direction perpendicular to the plane
• in stable room temperature

Determinants of lifting force in real conditions

In practice, the actual lifting capacity is determined by several key aspects, ranked from most significant:

• Gap between surfaces – even a fraction of a millimeter of distance (caused e.g. by veneer or dirt) diminishes the pulling force, often by half at just 0.5 mm.
• Force direction – declared lifting capacity refers to detachment vertically. When slipping, the magnet holds much less (often 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 reacts the same. Alloy additives weaken the attraction effect.
• Plate texture – ground elements guarantee perfect abutment, which improves field saturation. Rough surfaces weaken the grip.
• Operating temperature – NdFeB sinters have a sensitivity to temperature. When it is hot they lose power, and at low temperatures they can be stronger (up to a certain limit).

* Lifting capacity was assessed by applying a steel plate with a smooth surface of suitable thickness (min. 20 mm), under perpendicular pulling force, in contrast under attempts to slide the magnet the lifting capacity is smaller. In addition, even a small distance {between} the magnet’s surface and the plate reduces the lifting capacity.