BM 320x180x70 [4x M8] - magnetic beam

Pros as well as cons of NdFeB magnets.

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

• They do not lose strength, even after approximately 10 years – the reduction in power is only ~1% (based on measurements),
• They are resistant to demagnetization induced by external magnetic fields,
• By covering with a lustrous layer of nickel, the element gains an aesthetic look,
• They are known for high magnetic induction at the operating surface, making them more effective,
• 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...
• Possibility of custom forming and modifying to individual requirements,
• Key role in future technologies – they are commonly used in computer drives, electric motors, diagnostic systems, also complex engineering applications.
• Relatively small size with high pulling force – neodymium magnets offer high power in small dimensions, which allows their use in miniature devices

Disadvantages of neodymium magnets:

• At very strong impacts they can break, therefore we advise placing them in steel cases. A metal housing provides additional protection against damage, as well as increases the magnet's durability.
• When exposed to high temperature, neodymium magnets experience a drop in force. Often, when the temperature exceeds 80°C, their power decreases (depending on the size and shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
• Due to the susceptibility of magnets to corrosion in a humid environment, we suggest using waterproof magnets made of rubber, plastic or other material resistant to moisture, in case of application outdoors
• Limited ability of producing threads in the magnet and complicated forms - recommended is cover - mounting mechanism.
• Potential hazard resulting from small fragments of magnets pose a threat, if swallowed, which is particularly important in the aspect of protecting the youngest. Furthermore, small components of these devices can disrupt the diagnostic process medical in case of swallowing.
• Due to neodymium price, their price is relatively high,

Magnetic strength at its maximum – what contributes to it?

Holding force of 0 kg is a theoretical maximum value performed under specific, ideal conditions:

• using a sheet made of low-carbon steel, acting as a circuit closing element
• with a cross-section of at least 10 mm
• with an ideally smooth contact surface
• with total lack of distance (no paint)
• for force acting at a right angle (pull-off, not shear)
• in neutral thermal conditions

Lifting capacity in real conditions – factors

Effective lifting capacity is affected by working environment parameters, including (from priority):

• Clearance – the presence of foreign body (paint, dirt, gap) acts as an insulator, which lowers capacity steeply (even by 50% at 0.5 mm).
• Load vector – maximum parameter is available only during pulling at a 90° angle. The resistance to sliding of the magnet along the surface is usually several times lower (approx. 1/5 of the lifting capacity).
• Substrate thickness – to utilize 100% power, the steel must be adequately massive. Paper-thin metal limits the attraction force (the magnet "punches through" it).
• Plate material – low-carbon steel gives the best results. Alloy steels reduce magnetic properties and holding force.
• Surface structure – the more even the plate, the better the adhesion and higher the lifting capacity. Roughness acts like micro-gaps.
• Thermal factor – hot environment reduces magnetic field. Exceeding the limit temperature can permanently demagnetize the magnet.

* Lifting capacity was assessed with the use of a polished steel plate of suitable thickness (min. 20 mm), under perpendicular pulling force, whereas under attempts to slide the magnet the lifting capacity is smaller. Additionally, even a minimal clearance {between} the magnet and the plate decreases the holding force.