BM 320x180x70 [4x M8] - magnetic beam

Advantages as well as disadvantages of NdFeB magnets.

Besides their immense strength, neodymium magnets offer the following advantages:

• Their strength is durable, and after around ten years it drops only by ~1% (theoretically),
• Neodymium magnets are distinguished by extremely resistant to demagnetization caused by magnetic disturbances,
• By using a decorative layer of silver, the element acquires an aesthetic look,
• Neodymium magnets deliver maximum magnetic induction on a their surface, which increases force concentration,
• Neodymium magnets are characterized by very high magnetic induction on the magnet surface and can function (depending on the form) even at a temperature of 230°C or more...
• Thanks to the possibility of accurate molding and adaptation to individualized projects, NdFeB magnets can be produced in a variety of geometric configurations, which expands the range of possible applications,
• Versatile presence in innovative solutions – they serve a role in data components, drive modules, diagnostic systems, as well as other advanced devices.
• Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications

Disadvantages of neodymium magnets:

• At strong impacts they can break, therefore we recommend placing them in steel cases. A metal housing provides additional protection against damage, as well as increases the magnet's durability.
• We warn that neodymium magnets can reduce their power 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. For use outdoors we recommend using waterproof magnets e.g. in rubber, plastic
• Limited ability of producing nuts in the magnet and complex forms - preferred is a housing - magnet mounting.
• Potential hazard resulting from small fragments of magnets are risky, if swallowed, which is particularly important in the context of child safety. Additionally, tiny parts of these magnets are able to be problematic in diagnostics medical in case of swallowing.
• Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Detachment force of the magnet in optimal conditions – what it depends on?

Magnet power was defined for ideal contact conditions, including:

• using a plate made of mild steel, acting as a ideal flux conductor
• whose transverse dimension reaches at least 10 mm
• with a surface free of scratches
• with direct contact (without paint)
• under axial force vector (90-degree angle)
• in neutral thermal conditions

Determinants of practical lifting force of a magnet

In real-world applications, the real power is determined by many variables, ranked from the most important:

• Distance – the presence of foreign body (paint, tape, air) interrupts the magnetic circuit, which reduces power rapidly (even by 50% at 0.5 mm).
• Pull-off angle – remember that the magnet holds strongest perpendicularly. Under sliding down, the capacity drops significantly, often to levels of 20-30% of the maximum value.
• Metal thickness – the thinner the sheet, the weaker the hold. Magnetic flux passes through the material instead of generating force.
• Material type – ideal substrate is pure iron steel. Stainless steels may have worse magnetic properties.
• Surface finish – full contact is possible only on smooth steel. Rough texture create air cushions, weakening the magnet.
• Temperature – heating the magnet results in weakening of force. Check the thermal limit for a given model.

* Holding force was measured on a smooth steel plate of 20 mm thickness, when a perpendicular force was applied, whereas under attempts to slide the magnet the lifting capacity is smaller. Moreover, even a minimal clearance {between} the magnet and the plate reduces the holding force.