MPL 5x5x1.5 / N38 - lamellar magnet

Strengths as well as weaknesses of neodymium magnets.

Besides their immense pulling force, neodymium magnets offer the following advantages:

• They virtually do not lose strength, because even after ten years the performance loss is only ~1% (in laboratory conditions),
• They show high resistance to demagnetization induced by presence of other magnetic fields,
• A magnet with a metallic silver surface has better aesthetics,
• Magnetic induction on the working part of the magnet turns out to be impressive,
• Neodymium magnets are characterized by extremely high magnetic induction on the magnet surface and can work (depending on the form) even at a temperature of 230°C or more...
• Thanks to freedom in designing and the capacity to modify to complex applications,
• Fundamental importance in advanced technology sectors – they are used in hard drives, motor assemblies, medical devices, also modern systems.
• Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications

Problematic aspects of neodymium magnets: tips and applications.

• They are prone to damage upon too strong impacts. To avoid cracks, it is worth securing magnets in special housings. Such protection not only protects the magnet but also increases its resistance to damage
• Neodymium magnets lose force when exposed to high temperatures. After reaching 80°C, many of them experience permanent weakening of strength (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 very resistant to heat
• When exposed to humidity, magnets usually rust. For applications outside, it is recommended to use protective magnets, such as magnets in rubber or plastics, which secure oxidation and corrosion.
• Due to limitations in creating nuts and complicated shapes in magnets, we recommend using casing - magnetic holder.
• Possible danger related to microscopic parts of magnets can be dangerous, when accidentally swallowed, which is particularly important in the context of child safety. It is also worth noting that small elements of these magnets can disrupt the diagnostic process medical when they are in the body.
• High unit price – neodymium magnets are more expensive than other types of magnets (e.g. ferrite), which can limit application in large quantities

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

The force parameter is a result of laboratory testing performed under the following configuration:

• with the application of a sheet made of special test steel, guaranteeing maximum field concentration
• possessing a thickness of minimum 10 mm to ensure full flux closure
• characterized by smoothness
• without any insulating layer between the magnet and steel
• during detachment in a direction perpendicular to the plane
• at temperature room level

Magnet lifting force in use – key factors

Holding efficiency impacted by working environment parameters, such as (from priority):

• Gap between magnet and steel – every millimeter of distance (caused e.g. by veneer or unevenness) significantly weakens the magnet efficiency, often by half at just 0.5 mm.
• Pull-off angle – remember that the magnet holds strongest perpendicularly. Under sliding down, the capacity drops drastically, often to levels of 20-30% of the nominal value.
• Element thickness – for full efficiency, the steel must be sufficiently thick. Thin sheet limits the lifting capacity (the magnet "punches through" it).
• Material composition – different alloys reacts the same. High carbon content worsen the attraction effect.
• Surface structure – the more even the surface, the larger the contact zone and higher the lifting capacity. Unevenness acts like micro-gaps.
• Temperature – temperature increase causes a temporary drop of force. Check the maximum operating temperature for a given model.

* Holding force was tested on the plate surface of 20 mm thickness, when a perpendicular force was applied, whereas under attempts to slide the magnet the holding force is lower. Moreover, even a minimal clearance {between} the magnet’s surface and the plate decreases the holding force.