MPL 5x5x1.5 / N38 - lamellar magnet

Advantages as well as disadvantages of rare earth magnets.

Besides their exceptional field intensity, neodymium magnets offer the following advantages:

• Their power is maintained, and after approximately 10 years it decreases only by ~1% (theoretically),
• Neodymium magnets prove to be highly resistant to magnetic field loss caused by external interference,
• A magnet with a shiny silver surface has an effective appearance,
• Magnetic induction on the working part of the magnet turns out to be extremely intense,
• Due to their durability and thermal resistance, neodymium magnets are capable of operate (depending on the shape) even at high temperatures reaching 230°C or more...
• Possibility of exact machining as well as modifying to specific needs,
• Universal use in electronics industry – they are commonly used in magnetic memories, electric drive systems, medical equipment, and other advanced devices.
• Compactness – despite small sizes they provide effective action, making them ideal for precision applications

Disadvantages of neodymium magnets:

• They are prone to damage upon too strong impacts. To avoid cracks, it is worth securing magnets using a steel holder. Such protection not only shields the magnet but also improves its resistance to damage
• Neodymium magnets demagnetize when exposed to high temperatures. After reaching 80°C, many of them experience permanent weakening of power (a factor is the shape and dimensions of the magnet). We offer magnets specially adapted to work at temperatures up to 230°C marked [AH], which are extremely resistant to heat
• They rust in a humid environment - during 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 casing - magnetic mount.
• Potential hazard related to microscopic parts of magnets can be dangerous, if swallowed, which is particularly important in the context of child safety. Additionally, small components of these devices are able to disrupt the diagnostic process medical when they are in the body.
• With budget limitations the cost of neodymium magnets is economically unviable,

Best holding force of the magnet in ideal parameters – what affects it?

The declared magnet strength concerns the limit force, obtained under ideal test conditions, specifically:

• using a base made of low-carbon steel, serving as a circuit closing element
• possessing a thickness of minimum 10 mm to ensure full flux closure
• with a surface perfectly flat
• with direct contact (without impurities)
• for force applied at a right angle (pull-off, not shear)
• at standard ambient temperature

Lifting capacity in practice – influencing factors

Holding efficiency impacted by specific conditions, such as (from most important):

• Air gap (between the magnet and the plate), as even a tiny clearance (e.g. 0.5 mm) results in a reduction in force by up to 50% (this also applies to varnish, rust or debris).
• Angle of force application – highest force is available only during pulling at a 90° angle. The force required to slide of the magnet along the plate is typically many times smaller (approx. 1/5 of the lifting capacity).
• 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 type – ideal substrate is pure iron steel. Stainless steels may generate lower lifting capacity.
• Smoothness – full contact is obtained only on polished steel. Any scratches and bumps reduce the real contact area, weakening the magnet.
• Thermal environment – temperature increase causes a temporary drop of induction. It is worth remembering the thermal limit for a given model.

* Lifting capacity testing was carried out on plates with a smooth surface of suitable thickness, under perpendicular forces, whereas under parallel forces the load capacity is reduced by as much as 75%. In addition, even a small distance {between} the magnet’s surface and the plate lowers the holding force.