MW 5x15 / N38 - cylindrical magnet

Strengths as well as weaknesses of neodymium magnets.

In addition to their long-term stability, neodymium magnets provide the following advantages:

• Their strength is maintained, and after approximately 10 years it decreases only by ~1% (according to research),
• Neodymium magnets are characterized by exceptionally resistant to loss of magnetic properties caused by external field sources,
• By applying a lustrous coating of silver, the element gains an aesthetic look,
• They feature high magnetic induction at the operating surface, making them more effective,
• Neodymium magnets are characterized by very high magnetic induction on the magnet surface and can work (depending on the shape) even at a temperature of 230°C or more...
• Thanks to the ability of flexible shaping and adaptation to unique projects, neodymium magnets can be modeled in a variety of shapes and sizes, which makes them more universal,
• Universal use in modern industrial fields – they serve a role in mass storage devices, motor assemblies, advanced medical instruments, also complex engineering applications.
• Compactness – despite small sizes they provide effective action, making them ideal for precision applications

Disadvantages of NdFeB 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 increases its resistance to damage
• We warn that neodymium magnets can reduce their strength at high temperatures. To prevent this, we suggest our specialized [AH] magnets, which work effectively even at 230°C.
• They oxidize in a humid environment. For use outdoors we advise using waterproof magnets e.g. in rubber, plastic
• Limited ability of making threads in the magnet and complicated forms - preferred is casing - magnetic holder.
• Health risk to health – tiny shards of magnets are risky, in case of ingestion, which is particularly important in the context of child safety. Additionally, tiny parts of these products can disrupt the diagnostic process medical in case of swallowing.
• Due to neodymium price, their price is higher than average,

Magnetic strength at its maximum – what it depends on?

Holding force of 4.15 kg is a theoretical maximum value conducted under standard conditions:

• with the use of a sheet made of special test steel, guaranteeing maximum field concentration
• with a thickness minimum 10 mm
• characterized by lack of roughness
• with direct contact (no paint)
• for force applied at a right angle (in the magnet axis)
• at ambient temperature room level

Impact of factors on magnetic holding capacity in practice

Please note that the application force will differ subject to the following factors, in order of importance:

• Gap between magnet and steel – every millimeter of separation (caused e.g. by veneer or dirt) drastically reduces the pulling force, often by half at just 0.5 mm.
• Pull-off angle – note that the magnet holds strongest perpendicularly. Under shear forces, the holding force drops drastically, often to levels of 20-30% of the nominal value.
• Substrate thickness – for full efficiency, the steel must be sufficiently thick. Thin sheet restricts the lifting capacity (the magnet "punches through" it).
• Steel type – low-carbon steel attracts best. Alloy admixtures lower magnetic properties and holding force.
• Plate texture – ground elements guarantee perfect abutment, which increases field saturation. Uneven metal weaken the grip.
• Thermal environment – temperature increase causes a temporary drop of force. It is worth remembering the maximum operating temperature for a given model.

* Lifting capacity testing was conducted on a smooth plate of suitable thickness, under perpendicular forces, whereas under attempts to slide the magnet the lifting capacity is smaller. Moreover, even a small distance {between} the magnet and the plate decreases the load capacity.