SM 25x100 [2xM8] / N42 - magnetic separator

Advantages as well as disadvantages of NdFeB magnets.

Besides their exceptional magnetic power, neodymium magnets offer the following advantages:

• Their magnetic field remains stable, and after around 10 years it decreases only by ~1% (according to research),
• They show high resistance to demagnetization induced by external magnetic fields,
• In other words, due to the metallic surface of gold, the element gains a professional look,
• They feature high magnetic induction at the operating surface, making them more effective,
• 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 individual creating and optimizing to complex conditions,
• Huge importance in electronics industry – they are utilized in data components, electric motors, medical equipment, as well as other advanced devices.
• Thanks to their power density, small magnets offer high operating force, in miniature format,

What to avoid - cons of neodymium magnets: application proposals

• At very strong impacts they can break, therefore we recommend placing them in special holders. A metal housing provides additional protection against damage and increases the magnet's durability.
• Neodymium magnets decrease their power 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 stability even at temperatures up to 230°C
• They rust in a humid environment. For use outdoors we suggest using waterproof magnets e.g. in rubber, plastic
• Due to limitations in producing nuts and complex forms in magnets, we recommend using cover - magnetic holder.
• Potential hazard related to microscopic parts of magnets are risky, if swallowed, which is particularly important in the context of child safety. Furthermore, tiny parts of these magnets can disrupt the diagnostic process medical in case of swallowing.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

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

The load parameter shown refers to the peak performance, measured under laboratory conditions, meaning:

• with the application of a yoke made of low-carbon steel, guaranteeing full magnetic saturation
• possessing a massiveness of minimum 10 mm to ensure full flux closure
• with a plane free of scratches
• without the slightest insulating layer between the magnet and steel
• for force acting at a right angle (pull-off, not shear)
• in neutral thermal conditions

Practical lifting capacity: influencing factors

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

• Distance (between the magnet and the metal), as even a very small distance (e.g. 0.5 mm) results in a reduction in lifting capacity by up to 50% (this also applies to varnish, rust or dirt).
• Pull-off angle – note that the magnet has greatest strength perpendicularly. Under sliding down, the holding force drops significantly, often to levels of 20-30% of the nominal value.
• Base massiveness – too thin plate does not accept the full field, causing part of the power to be escaped into the air.
• Material composition – not every steel attracts identically. High carbon content worsen the attraction effect.
• Surface quality – the more even the surface, the larger the contact zone and higher the lifting capacity. Unevenness acts like micro-gaps.
• Operating temperature – NdFeB sinters have a negative temperature coefficient. At higher temperatures they lose power, and at low temperatures they can be stronger (up to a certain limit).

* Lifting capacity testing was carried out on a smooth plate of optimal thickness, under perpendicular forces, in contrast under parallel forces the lifting capacity is smaller. Additionally, even a minimal clearance {between} the magnet’s surface and the plate lowers the load capacity.