SM 32x500 [2xM8] / N42 - magnetic separator

Strengths as well as weaknesses of NdFeB magnets.

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

• Their magnetic field is durable, and after approximately ten years it drops only by ~1% (according to research),
• Neodymium magnets are remarkably resistant to magnetic field loss caused by external magnetic fields,
• The use of an elegant finish of noble metals (nickel, gold, silver) causes the element to be more visually attractive,
• Neodymium magnets deliver maximum magnetic induction on a small area, which increases force concentration,
• 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...
• Due to the possibility of flexible molding and adaptation to individualized needs, neodymium magnets can be modeled in a broad palette of forms and dimensions, which expands the range of possible applications,
• Universal use in modern technologies – they are utilized in computer drives, electromotive mechanisms, medical equipment, and complex engineering applications.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

Drawbacks and weaknesses of neodymium magnets: tips and applications.

• Susceptibility to cracking is one of their disadvantages. Upon intense impact they can fracture. We advise keeping them in a steel housing, which not only protects them against impacts but also raises their 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
• They oxidize in a humid environment - during use outdoors we advise using waterproof magnets e.g. in rubber, plastic
• Due to limitations in creating threads and complex forms in magnets, we propose using cover - magnetic holder.
• Potential hazard to health – tiny shards of magnets can be dangerous, when accidentally swallowed, which is particularly important in the context of child health protection. It is also worth noting that tiny parts of these devices are able to disrupt the diagnostic process medical after entering the body.
• High unit price – neodymium magnets cost more than other types of magnets (e.g. ferrite), which increases costs of application in large quantities

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

The specified lifting capacity concerns the maximum value, measured under laboratory conditions, namely:

• on a base made of mild steel, optimally conducting the magnetic field
• possessing a thickness of minimum 10 mm to avoid saturation
• with an ground touching surface
• with zero gap (no paint)
• during pulling in a direction vertical to the mounting surface
• in stable room temperature

Determinants of lifting force in real conditions

Effective lifting capacity is affected by specific conditions, mainly (from priority):

• Distance – existence of foreign body (paint, tape, air) interrupts the magnetic circuit, which reduces power rapidly (even by 50% at 0.5 mm).
• Direction of force – maximum parameter is reached only during pulling at a 90° angle. The shear force of the magnet along the plate is typically several times lower (approx. 1/5 of the lifting capacity).
• Base massiveness – insufficiently thick sheet does not close the flux, causing part of the power to be escaped into the air.
• Material composition – different alloys reacts the same. High carbon content weaken the attraction effect.
• Surface finish – ideal contact is obtained only on smooth steel. Any scratches and bumps reduce the real contact area, weakening the magnet.
• Temperature influence – hot environment reduces pulling force. Exceeding the limit temperature can permanently demagnetize the magnet.

* Lifting capacity testing was conducted on plates with a smooth surface of optimal thickness, under a perpendicular pulling force, whereas under attempts to slide the magnet the lifting capacity is smaller. In addition, even a slight gap {between} the magnet and the plate reduces the load capacity.