MW 29x10 / N38 - cylindrical magnet

Advantages as well as disadvantages of rare earth magnets.

Apart from their strong power, neodymium magnets have these key benefits:

• Their magnetic field is durable, and after around 10 years it decreases only by ~1% (according to research),
• Neodymium magnets are characterized by highly resistant to loss of magnetic properties caused by external magnetic fields,
• In other words, due to the glossy layer of gold, the element looks attractive,
• Magnetic induction on the top side of the magnet is maximum,
• Due to their durability and thermal resistance, neodymium magnets can operate (depending on the form) even at high temperatures reaching 230°C or more...
• Due to the option of precise molding and adaptation to custom projects, magnetic components can be manufactured in a broad palette of forms and dimensions, which increases their versatility,
• Versatile presence in high-tech industry – they are used in mass storage devices, electromotive mechanisms, precision medical tools, as well as multitasking production systems.
• Compactness – despite small sizes they provide effective action, making them ideal for precision applications

Drawbacks and weaknesses of neodymium magnets: application proposals

• To avoid cracks under impact, we recommend using special steel housings. Such a solution protects the magnet and simultaneously improves its durability.
• Neodymium magnets lose their force 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 rust in a humid environment - during use outdoors we recommend using waterproof magnets e.g. in rubber, plastic
• Limited ability of producing nuts in the magnet and complicated forms - recommended is casing - magnet mounting.
• Possible danger related to microscopic parts of magnets pose a threat, in case of ingestion, which gains importance in the aspect of protecting the youngest. Furthermore, small components of these products are able to disrupt the diagnostic process medical in case of swallowing.
• Due to complex production process, their price exceeds standard values,

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

Information about lifting capacity was determined for the most favorable conditions, assuming:

• with the contact of a sheet made of special test steel, ensuring maximum field concentration
• whose transverse dimension reaches at least 10 mm
• with an ideally smooth touching surface
• under conditions of gap-free contact (surface-to-surface)
• during pulling in a direction perpendicular to the plane
• at room temperature

Impact of factors on magnetic holding capacity in practice

Holding efficiency is influenced by specific conditions, including (from priority):

• Distance – the presence of foreign body (paint, dirt, gap) interrupts the magnetic circuit, which lowers power steeply (even by 50% at 0.5 mm).
• Pull-off angle – remember that the magnet holds strongest perpendicularly. Under shear forces, the capacity drops drastically, often to levels of 20-30% of the maximum value.
• Base massiveness – too thin steel does not accept the full field, causing part of the power to be escaped into the air.
• Material composition – different alloys attracts identically. Alloy additives worsen the attraction effect.
• Plate texture – smooth surfaces guarantee perfect abutment, which improves field saturation. Rough surfaces weaken the grip.
• Operating temperature – neodymium magnets have a sensitivity to temperature. When it is hot they are weaker, and in frost gain strength (up to a certain limit).

* Lifting capacity testing was carried out on plates with a smooth surface of suitable thickness, under perpendicular forces, whereas under shearing force the holding force is lower. In addition, even a slight gap {between} the magnet and the plate decreases the load capacity.