SMZR 32x150 / N52 - magnetic separator with handle

Advantages as well as disadvantages of neodymium magnets.

Besides their immense strength, neodymium magnets offer the following advantages:

• They retain full power for around ten years – the loss is just ~1% (in theory),
• They are extremely resistant to demagnetization induced by external disturbances,
• In other words, due to the metallic surface of gold, the element gains a professional look,
• Neodymium magnets create maximum magnetic induction on a their surface, which ensures high operational effectiveness,
• Through (appropriate) combination of ingredients, they can achieve high thermal strength, enabling action at temperatures reaching 230°C and above...
• Thanks to the possibility of flexible shaping and adaptation to unique solutions, neodymium magnets can be manufactured in a broad palette of forms and dimensions, which expands the range of possible applications,
• Huge importance in future technologies – they serve a role in mass storage devices, electric motors, medical devices, as well as technologically advanced constructions.
• Thanks to concentrated force, small magnets offer high operating force, with minimal size,

Disadvantages of neodymium magnets:

• To avoid cracks under impact, we recommend using special steel housings. Such a solution protects the magnet and simultaneously improves its durability.
• When exposed to high temperature, neodymium magnets experience a drop in strength. Often, when the temperature exceeds 80°C, their power decreases (depending on the size and shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
• Due to the susceptibility of magnets to corrosion in a humid environment, we suggest using waterproof magnets made of rubber, plastic or other material immune to moisture, when using outdoors
• Limited possibility of creating nuts in the magnet and complex forms - preferred is cover - mounting mechanism.
• Possible danger related to microscopic parts of magnets are risky, if swallowed, which gains importance in the context of child health protection. Furthermore, small components of these magnets can disrupt the diagnostic process medical in case of swallowing.
• High unit price – neodymium magnets are more expensive than other types of magnets (e.g. ferrite), which increases costs of application in large quantities

Optimal lifting capacity of a neodymium magnet – what it depends on?

The force parameter is a measurement result performed under standard conditions:

• using a base made of low-carbon steel, serving as a circuit closing element
• with a cross-section no less than 10 mm
• with an polished contact surface
• without any clearance between the magnet and steel
• under vertical force direction (90-degree angle)
• in stable room temperature

Key elements affecting lifting force

In real-world applications, the actual lifting capacity is determined by several key aspects, ranked from most significant:

• Space between magnet and steel – every millimeter of separation (caused e.g. by varnish or dirt) drastically reduces 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 exhibits significantly lower power (typically approx. 20-30% of maximum force).
• Steel thickness – too thin sheet causes magnetic saturation, causing part of the flux to be wasted into the air.
• Plate material – low-carbon steel attracts best. Higher carbon content reduce magnetic permeability and lifting capacity.
• Surface finish – ideal contact is possible only on smooth steel. Any scratches and bumps create air cushions, reducing force.
• Temperature – temperature increase results in weakening of force. It is worth remembering the thermal limit for a given model.

* Lifting capacity testing was carried out on a smooth plate of suitable thickness, under perpendicular forces, however under shearing force the lifting capacity is smaller. In addition, even a minimal clearance {between} the magnet’s surface and the plate decreases the lifting capacity.