UMH 42x9x46 [M6] / N38 - magnetic holder with hook

Pros as well as cons of NdFeB magnets.

Besides their high retention, neodymium magnets are valued for these benefits:

• They do not lose power, even during nearly 10 years – the decrease in lifting capacity is only ~1% (based on measurements),
• They are noted for resistance to demagnetization induced by presence of other magnetic fields,
• A magnet with a metallic gold surface looks better,
• Magnets possess exceptionally strong magnetic induction on the active area,
• 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...
• Due to the potential of free forming and adaptation to unique projects, magnetic components can be manufactured in a variety of geometric configurations, which makes them more universal,
• Significant place in advanced technology sectors – they are utilized in mass storage devices, electric motors, medical devices, also other advanced devices.
• Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications

Problematic aspects of neodymium magnets and ways of using them

• They are fragile upon too strong impacts. To avoid cracks, it is worth protecting magnets in special housings. Such protection not only protects the magnet but also improves its resistance to damage
• We warn that neodymium magnets can reduce their power at high temperatures. To prevent this, we advise our specialized [AH] magnets, which work effectively even at 230°C.
• They rust in a humid environment - during use outdoors we recommend using waterproof magnets e.g. in rubber, plastic
• We suggest a housing - magnetic mechanism, due to difficulties in realizing nuts inside the magnet and complicated forms.
• Possible danger related to microscopic parts of magnets can be dangerous, when accidentally swallowed, which gains importance in the aspect of protecting the youngest. Additionally, small components of these products can be problematic in diagnostics medical after entering the body.
• Due to expensive raw materials, their price is relatively high,

Highest magnetic holding force – what it depends on?

Information about lifting capacity was defined for ideal contact conditions, including:

• on a base made of structural steel, perfectly concentrating the magnetic flux
• possessing a thickness of min. 10 mm to ensure full flux closure
• with an polished contact surface
• under conditions of ideal adhesion (surface-to-surface)
• under axial application of breakaway force (90-degree angle)
• in stable room temperature

Practical aspects of lifting capacity – factors

In real-world applications, the real power depends on many variables, presented from the most important:

• Distance (betwixt the magnet and the metal), since even a very small distance (e.g. 0.5 mm) leads to a drastic drop in force by up to 50% (this also applies to varnish, rust or dirt).
• Force direction – note that the magnet holds strongest perpendicularly. Under sliding down, the capacity drops significantly, often to levels of 20-30% of the nominal value.
• Steel thickness – insufficiently thick sheet does not close the flux, causing part of the power to be escaped to the other side.
• Material type – ideal substrate is pure iron steel. Hardened steels may generate lower lifting capacity.
• Smoothness – ideal contact is obtained only on polished steel. Any scratches and bumps create air cushions, reducing force.
• Temperature – heating the magnet results in weakening of force. It is worth remembering the maximum operating temperature for a given model.

* Lifting capacity testing was performed on plates with a smooth surface of optimal thickness, under perpendicular forces, in contrast under parallel forces the holding force is lower. In addition, even a slight gap {between} the magnet’s surface and the plate reduces the lifting capacity.