MPL 50x20x5 / N38 - lamellar magnet

Advantages as well as disadvantages of rare earth magnets.

Besides their magnetic performance, neodymium magnets are valued for these benefits:

• They retain full power for almost 10 years – the drop is just ~1% (based on simulations),
• They are resistant to demagnetization induced by presence of other magnetic fields,
• By using a reflective layer of gold, the element presents an modern look,
• Neodymium magnets create 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 shape) at temperatures up to 230°C and above...
• Possibility of individual forming as well as adapting to precise conditions,
• Universal use in advanced technology sectors – they are commonly used in mass storage devices, electromotive mechanisms, diagnostic systems, also complex engineering applications.
• Thanks to efficiency per cm³, small magnets offer high operating force, in miniature format,

Disadvantages of neodymium magnets:

• They are prone to damage upon too strong impacts. To avoid cracks, it is worth protecting magnets using a steel holder. Such protection not only shields the magnet but also improves its resistance to damage
• Neodymium magnets lose their strength under the influence of heating. As soon as 80°C is exceeded, many of them start losing their force. Therefore, we recommend our special magnets marked [AH], which maintain durability even at temperatures 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 nuts and complicated forms in magnets, we recommend using a housing - magnetic mechanism.
• Potential hazard to health – tiny shards of magnets can be dangerous, if swallowed, which gains importance in the context of child safety. Furthermore, small elements of these magnets are able to disrupt the diagnostic process medical in case of swallowing.
• Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Magnetic strength at its maximum – what affects it?

Information about lifting capacity was defined for optimal configuration, including:

• on a plate made of mild steel, perfectly concentrating the magnetic field
• with a thickness no less than 10 mm
• characterized by smoothness
• under conditions of ideal adhesion (surface-to-surface)
• under vertical application of breakaway force (90-degree angle)
• at standard ambient temperature

What influences lifting capacity in practice

During everyday use, the actual lifting capacity is determined by many variables, listed from most significant:

• Clearance – existence of foreign body (paint, dirt, gap) acts as an insulator, which reduces capacity steeply (even by 50% at 0.5 mm).
• Loading method – declared lifting capacity refers to detachment vertically. When slipping, the magnet exhibits significantly lower power (typically approx. 20-30% of nominal force).
• Metal thickness – thin material does not allow full use of the magnet. Magnetic flux passes through the material instead of converting into lifting capacity.
• Material composition – different alloys attracts identically. Alloy additives worsen the interaction with the magnet.
• Smoothness – full contact is possible only on polished steel. Rough texture reduce the real contact area, weakening the magnet.
• Temperature – temperature increase results in weakening of induction. It is worth remembering the thermal limit for a given model.

* Holding force was checked on the plate surface of 20 mm thickness, when the force acted perpendicularly, in contrast under attempts to slide the magnet the lifting capacity is smaller. Moreover, even a slight gap {between} the magnet and the plate reduces the lifting capacity.