MP 5x2.7/1.2x5 C / N38 - ring magnet

Strengths and weaknesses of neodymium magnets.

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

• They retain full power for almost 10 years – the drop is just ~1% (according to analyses),
• They have excellent resistance to magnetism drop as a result of opposing magnetic fields,
• A magnet with a metallic silver surface has an effective appearance,
• Magnets have very high magnetic induction on the outer layer,
• Neodymium magnets are characterized by extremely high magnetic induction on the magnet surface and can function (depending on the form) even at a temperature of 230°C or more...
• Due to the potential of precise molding and customization to individualized projects, neodymium magnets can be produced in a wide range of shapes and sizes, which increases their versatility,
• Huge importance in modern industrial fields – they are used in magnetic memories, electric motors, medical equipment, as well as technologically advanced constructions.
• Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications

Disadvantages of neodymium magnets:

• Susceptibility to cracking is one of their disadvantages. Upon strong impact they can break. We advise keeping them in a steel housing, which not only protects them against impacts but also increases their 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 durability even at temperatures up to 230°C
• They oxidize in a humid environment. For use outdoors we advise using waterproof magnets e.g. in rubber, plastic
• Due to limitations in realizing nuts and complex forms in magnets, we recommend using casing - magnetic mechanism.
• Possible danger related to microscopic parts of magnets pose a threat, if swallowed, which is particularly important in the context of child safety. Furthermore, tiny parts of these devices are able to be problematic in diagnostics medical after entering the body.
• Due to expensive raw materials, their price exceeds standard values,

Magnetic strength at its maximum – what it depends on?

The lifting capacity listed is a theoretical maximum value conducted under the following configuration:

• using a base made of low-carbon steel, functioning as a ideal flux conductor
• with a cross-section no less than 10 mm
• characterized by smoothness
• without any clearance between the magnet and steel
• under axial force direction (90-degree angle)
• at ambient temperature room level

Practical lifting capacity: influencing factors

During everyday use, the actual lifting capacity results from several key aspects, ranked from crucial:

• Distance (between the magnet and the plate), 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, rust or debris).
• Load vector – maximum parameter is obtained only during perpendicular pulling. The force required to slide of the magnet along the surface is usually several times lower (approx. 1/5 of the lifting capacity).
• Plate thickness – too thin sheet causes magnetic saturation, causing part of the power to be wasted into the air.
• Steel type – mild steel attracts best. Higher carbon content decrease magnetic properties and holding force.
• Surface finish – full contact is obtained only on polished steel. Any scratches and bumps create air cushions, weakening the magnet.
• Thermal factor – high temperature weakens pulling force. Exceeding the limit temperature can permanently demagnetize the magnet.

* Holding force was checked on the plate surface of 20 mm thickness, when a perpendicular force was applied, however under parallel forces the load capacity is reduced by as much as 75%. Moreover, even a slight gap {between} the magnet’s surface and the plate decreases the load capacity.