MW 14x10 / N38 - cylindrical magnet

Strengths and weaknesses of rare earth magnets.

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

• They do not lose power, even over nearly 10 years – the drop in lifting capacity is only ~1% (based on measurements),
• Neodymium magnets remain extremely resistant to magnetic field loss caused by magnetic disturbances,
• Thanks to the elegant finish, the layer of Ni-Cu-Ni, gold-plated, or silver-plated gives an elegant appearance,
• The surface of neodymium magnets generates a strong magnetic field – this is a key feature,
• Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their shape) at temperatures up to 230°C and above...
• Thanks to flexibility in shaping and the ability to customize to individual projects,
• Universal use in advanced technology sectors – they serve a role in HDD drives, electric drive systems, advanced medical instruments, and multitasking production systems.
• Thanks to efficiency per cm³, small magnets offer high operating force, with minimal size,

Problematic aspects of neodymium magnets and proposals for their use:

• They are fragile upon heavy impacts. To avoid cracks, it is worth securing magnets in a protective case. Such protection not only protects 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 - during use outdoors we advise using waterproof magnets e.g. in rubber, plastic
• Due to limitations in producing threads and complicated shapes in magnets, we recommend using cover - magnetic mechanism.
• Possible danger to health – tiny shards of magnets can be dangerous, when accidentally swallowed, which is particularly important in the context of child safety. Furthermore, tiny parts of these products are able to be problematic in diagnostics medical in case of swallowing.
• With budget limitations the cost of neodymium magnets can be a barrier,

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

Breakaway force was determined for the most favorable conditions, taking into account:

• using a sheet made of low-carbon steel, functioning as a circuit closing element
• whose thickness equals approx. 10 mm
• with a surface cleaned and smooth
• with direct contact (without paint)
• under vertical force direction (90-degree angle)
• in temp. approx. 20°C

Determinants of lifting force in real conditions

Effective lifting capacity is affected by specific conditions, such as (from priority):

• Gap (between the magnet and the plate), because even a microscopic distance (e.g. 0.5 mm) leads to a decrease in lifting capacity by up to 50% (this also applies to varnish, corrosion or dirt).
• Force direction – note that the magnet has greatest strength perpendicularly. Under shear forces, the holding force drops drastically, often to levels of 20-30% of the maximum value.
• Substrate thickness – for full efficiency, the steel must be adequately massive. Paper-thin metal restricts the attraction force (the magnet "punches through" it).
• Material composition – not every steel attracts identically. Alloy additives worsen the attraction effect.
• Plate texture – ground elements ensure maximum contact, which improves force. Uneven metal reduce efficiency.
• Heat – neodymium magnets have a sensitivity to temperature. At higher temperatures they are weaker, and at low temperatures they can be stronger (up to a certain limit).

* Lifting capacity testing was carried out on plates with a smooth surface of optimal thickness, under a perpendicular pulling force, in contrast under shearing force the holding force is lower. In addition, even a small distance {between} the magnet’s surface and the plate decreases the load capacity.