UMH 48x11x65 [M6] / N38 - magnetic holder with hook

Advantages as well as disadvantages of NdFeB magnets.

Apart from their superior magnetism, neodymium magnets have these key benefits:

• Their power is maintained, and after around 10 years it drops only by ~1% (according to research),
• Magnets effectively protect themselves against demagnetization caused by foreign field sources,
• Thanks to the glossy finish, the coating of nickel, gold-plated, or silver-plated gives an aesthetic appearance,
• Neodymium magnets achieve maximum magnetic induction on a contact point, which ensures high operational effectiveness,
• Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their form) at temperatures up to 230°C and above...
• Possibility of individual shaping and adjusting to defined conditions,
• Key role in high-tech industry – they are commonly used in mass storage devices, electromotive mechanisms, diagnostic systems, and technologically advanced constructions.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in compact dimensions, which enables their usage in compact constructions

Cons of neodymium magnets: tips and applications.

• Susceptibility to cracking is one of their disadvantages. Upon strong impact they can fracture. We advise keeping them in a special holder, which not only protects them against impacts but also increases their durability
• 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 advise using waterproof magnets e.g. in rubber, plastic
• Limited possibility of creating nuts in the magnet and complex forms - preferred is a housing - magnetic holder.
• Potential hazard to health – tiny shards of magnets are risky, in case of ingestion, which gains importance in the context of child health protection. Furthermore, small elements of these devices are able to disrupt the diagnostic process medical in case of swallowing.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

Highest magnetic holding force – what affects it?

The specified lifting capacity represents the limit force, obtained under ideal test conditions, namely:

• with the contact of a sheet made of low-carbon steel, ensuring full magnetic saturation
• whose thickness reaches at least 10 mm
• with an ground contact surface
• with direct contact (no coatings)
• under axial application of breakaway force (90-degree angle)
• at ambient temperature approx. 20 degrees Celsius

Key elements affecting lifting force

Bear in mind that the application force will differ depending on elements below, starting with the most relevant:

• Gap between surfaces – even a fraction of a millimeter of distance (caused e.g. by varnish or dirt) significantly weakens the magnet efficiency, often by half at just 0.5 mm.
• Loading method – catalog parameter refers to pulling vertically. When slipping, the magnet exhibits significantly lower power (typically approx. 20-30% of nominal force).
• Plate thickness – insufficiently thick sheet does not accept the full field, causing part of the power to be lost to the other side.
• Material type – ideal substrate is pure iron steel. Hardened steels may generate lower lifting capacity.
• Surface quality – the more even the plate, the larger the contact zone and higher the lifting capacity. Unevenness creates an air distance.
• Thermal environment – temperature increase results in weakening of induction. It is worth remembering the thermal limit for a given model.

* Lifting capacity was assessed by applying a polished steel plate of optimal thickness (min. 20 mm), under perpendicular detachment force, in contrast under parallel forces the load capacity is reduced by as much as 5 times. Additionally, even a minimal clearance {between} the magnet’s surface and the plate decreases the load capacity.