SM 25x325 [2xM8] / N52 - magnetic separator

Pros and cons of neodymium magnets.

Besides their stability, neodymium magnets are valued for these benefits:

• They do not lose power, even during around 10 years – the decrease in lifting capacity is only ~1% (based on measurements),
• Neodymium magnets are characterized by remarkably resistant to demagnetization caused by magnetic disturbances,
• The use of an aesthetic coating of noble metals (nickel, gold, silver) causes the element to have aesthetics,
• Magnets possess impressive magnetic induction on the surface,
• Thanks to resistance to high temperature, they can operate (depending on the shape) even at temperatures up to 230°C and higher...
• Thanks to freedom in forming and the ability to modify to client solutions,
• Fundamental importance in future technologies – they find application in hard drives, drive modules, diagnostic systems, and technologically advanced constructions.
• Thanks to efficiency per cm³, small magnets offer high operating force, occupying minimum space,

Disadvantages of neodymium magnets:

• At very strong impacts they can break, therefore we advise placing them in steel cases. 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 power. Therefore, we recommend our special magnets marked [AH], which maintain stability even at temperatures up to 230°C
• They oxidize in a humid environment - during use outdoors we recommend using waterproof magnets e.g. in rubber, plastic
• We recommend casing - magnetic holder, due to difficulties in realizing threads inside the magnet and complicated forms.
• Possible danger related to microscopic parts of magnets are risky, if swallowed, which becomes key in the aspect of protecting the youngest. Furthermore, small components of these products can be problematic in diagnostics medical when they are in the body.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

Maximum lifting capacity of the magnet – what contributes to it?

Holding force of 0 kg is a result of laboratory testing executed under the following configuration:

• using a plate made of high-permeability steel, serving as a magnetic yoke
• with a cross-section of at least 10 mm
• with a plane cleaned and smooth
• with direct contact (no paint)
• during detachment in a direction perpendicular to the mounting surface
• at temperature room level

Key elements affecting lifting force

Effective lifting capacity impacted by specific conditions, mainly (from most important):

• Air gap (between the magnet and the metal), because even a microscopic distance (e.g. 0.5 mm) results in a drastic drop in lifting capacity by up to 50% (this also applies to varnish, corrosion or dirt).
• Loading method – declared lifting capacity refers to detachment vertically. When attempting to slide, the magnet holds significantly lower power (often approx. 20-30% of maximum force).
• Wall thickness – thin material does not allow full use of the magnet. Magnetic flux passes through the material instead of converting into lifting capacity.
• Material composition – not every steel reacts the same. Alloy additives worsen the attraction effect.
• Surface finish – ideal contact is obtained only on smooth steel. Rough texture reduce the real contact area, reducing force.
• Temperature – temperature increase results in weakening of induction. Check the thermal limit for a given model.

* Lifting capacity testing was conducted on plates with a smooth surface of suitable thickness, under perpendicular forces, however under attempts to slide the magnet the lifting capacity is smaller. Additionally, even a small distance {between} the magnet’s surface and the plate reduces the lifting capacity.