SMZR 32x225 / N52 - magnetic separator with handle

Advantages as well as disadvantages of neodymium magnets.

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

• They have unchanged lifting capacity, and over more than 10 years their performance decreases symbolically – ~1% (according to theory),
• They maintain their magnetic properties even under strong external field,
• A magnet with a metallic silver surface has better aesthetics,
• The surface of neodymium magnets generates a powerful magnetic field – this is one of their assets,
• Through (appropriate) combination of ingredients, they can achieve high thermal strength, enabling functioning at temperatures reaching 230°C and above...
• In view of the ability of free molding and adaptation to individualized requirements, magnetic components can be modeled in a variety of shapes and sizes, which expands the range of possible applications,
• Key role in modern technologies – they serve a role in computer drives, brushless drives, medical equipment, also modern systems.
• Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in compact dimensions, which allows their use in small systems

Disadvantages of neodymium magnets:

• To avoid cracks upon strong impacts, we recommend using special steel housings. Such a solution secures the magnet and simultaneously increases its durability.
• We warn that neodymium magnets can reduce their power at high temperatures. To prevent this, we recommend our specialized [AH] magnets, which work effectively even at 230°C.
• Due to the susceptibility of magnets to corrosion in a humid environment, we recommend using waterproof magnets made of rubber, plastic or other material resistant to moisture, in case of application outdoors
• Due to limitations in realizing nuts and complicated forms in magnets, we recommend using a housing - magnetic mechanism.
• Possible danger to health – tiny shards of magnets can be dangerous, if swallowed, which gains importance in the context of child health protection. It is also worth noting that small elements of these products can disrupt the diagnostic process medical when they are in the body.
• High unit price – neodymium magnets have a higher price than other types of magnets (e.g. ferrite), which can limit application in large quantities

Highest magnetic holding force – what it depends on?

The force parameter is a theoretical maximum value conducted under the following configuration:

• using a base made of mild steel, functioning as a circuit closing element
• with a cross-section minimum 10 mm
• with a surface free of scratches
• under conditions of no distance (surface-to-surface)
• under vertical force direction (90-degree angle)
• in stable room temperature

Key elements affecting lifting force

Bear in mind that the working load may be lower depending on the following factors, in order of importance:

• Clearance – existence of any layer (paint, dirt, gap) acts as an insulator, which reduces capacity rapidly (even by 50% at 0.5 mm).
• Force direction – declared lifting capacity refers to detachment vertically. When applying parallel force, the magnet holds significantly lower power (often approx. 20-30% of maximum force).
• Base massiveness – too thin sheet does not accept the full field, causing part of the power to be escaped to the other side.
• Material composition – not every steel reacts the same. Alloy additives worsen the attraction effect.
• Base smoothness – the smoother and more polished the plate, the better the adhesion and higher the lifting capacity. Roughness creates an air distance.
• Temperature influence – high temperature reduces magnetic field. Too high temperature can permanently damage the magnet.

* Lifting capacity was measured with the use of a polished steel plate of optimal thickness (min. 20 mm), under perpendicular pulling force, whereas under attempts to slide the magnet the holding force is lower. Moreover, even a small distance {between} the magnet’s surface and the plate lowers the holding force.