ZM XMAG2 105 elementów - magnetic toy

Strengths and weaknesses of rare earth magnets.

In addition to their magnetic capacity, neodymium magnets provide the following advantages:

• They do not lose magnetism, even during approximately 10 years – the reduction in strength is only ~1% (according to tests),
• Magnets perfectly defend themselves against loss of magnetization caused by ambient magnetic noise,
• In other words, due to the aesthetic layer of gold, the element gains visual value,
• Neodymium magnets deliver maximum magnetic induction on a their surface, which increases force concentration,
• Thanks to resistance to high temperature, they are able to function (depending on the shape) even at temperatures up to 230°C and higher...
• Thanks to versatility in forming and the capacity to modify to client solutions,
• Significant place in high-tech industry – they are used in hard drives, brushless drives, advanced medical instruments, and industrial machines.
• Thanks to their power density, small magnets offer high operating force, in miniature format,

Disadvantages of NdFeB magnets:

• Brittleness is one of their disadvantages. Upon strong impact they can break. We recommend 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 strength at high temperatures. To prevent this, we recommend our specialized [AH] magnets, which work effectively even at 230°C.
• Due to the susceptibility of magnets to corrosion in a humid environment, we advise using waterproof magnets made of rubber, plastic or other material resistant to moisture, in case of application outdoors
• Due to limitations in producing nuts and complicated shapes in magnets, we propose using a housing - magnetic mount.
• Potential hazard related to microscopic parts of magnets are risky, when accidentally swallowed, which becomes key in the context of child health protection. Additionally, tiny parts of these devices can complicate diagnosis medical after entering the body.
• With large orders the cost of neodymium magnets is a challenge,

Maximum lifting force for a neodymium magnet – what it depends on?

The declared magnet strength concerns the peak performance, measured under optimal environment, specifically:

• using a plate made of mild steel, acting as a circuit closing element
• possessing a thickness of minimum 10 mm to ensure full flux closure
• with an ground touching surface
• under conditions of no distance (metal-to-metal)
• during pulling in a direction vertical to the plane
• at ambient temperature room level

Key elements affecting lifting force

Holding efficiency is affected by working environment parameters, such as (from most important):

• Clearance – the presence of any layer (rust, tape, gap) interrupts the magnetic circuit, which lowers capacity rapidly (even by 50% at 0.5 mm).
• Pull-off angle – remember that the magnet has greatest strength perpendicularly. Under sliding down, the capacity drops significantly, often to levels of 20-30% of the nominal value.
• Steel thickness – too thin plate causes magnetic saturation, causing part of the flux to be wasted into the air.
• Plate material – low-carbon steel gives the best results. Alloy steels reduce magnetic permeability and lifting capacity.
• Surface finish – ideal contact is possible only on polished steel. Any scratches and bumps reduce the real contact area, weakening the magnet.
• Thermal factor – high temperature reduces pulling force. Too high temperature can permanently demagnetize the magnet.

* Lifting capacity was measured using a steel plate with a smooth surface of optimal thickness (min. 20 mm), under perpendicular detachment force, in contrast under attempts to slide the magnet the holding force is lower. Additionally, even a minimal clearance {between} the magnet’s surface and the plate reduces the holding force.