CM PML-10 / N45 - magnetic gripper

Strengths and weaknesses of rare earth magnets.

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

• They virtually do not lose power, because even after 10 years the performance loss is only ~1% (in laboratory conditions),
• Magnets very well defend themselves against demagnetization caused by ambient magnetic noise,
• Thanks to the shimmering finish, the surface of Ni-Cu-Ni, gold-plated, or silver-plated gives an modern appearance,
• Magnetic induction on the surface of the magnet is impressive,
• 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...
• Thanks to flexibility in forming and the capacity to modify to complex applications,
• Versatile presence in innovative solutions – they are commonly used in magnetic memories, electromotive mechanisms, precision medical tools, also industrial machines.
• Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications

Disadvantages of neodymium magnets:

• They are fragile upon too strong impacts. To avoid cracks, it is worth securing magnets in a protective case. Such protection not only protects the magnet but also increases its resistance to damage
• When exposed to high temperature, neodymium magnets experience a drop in power. Often, when the temperature exceeds 80°C, their power decreases (depending on the size, as well as 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 recommend using waterproof magnets e.g. in rubber, plastic
• Due to limitations in creating threads and complex shapes in magnets, we recommend using casing - magnetic holder.
• Health risk resulting from small fragments of magnets can be dangerous, in case of ingestion, which becomes key in the context of child safety. It is also worth noting that small components of these magnets can complicate diagnosis medical in case of swallowing.
• With large orders the cost of neodymium magnets is a challenge,

Maximum lifting force for a neodymium magnet – what contributes to it?

The specified lifting capacity concerns the limit force, recorded under ideal test conditions, meaning:

• with the application of a sheet made of low-carbon steel, ensuring maximum field concentration
• possessing a thickness of min. 10 mm to avoid saturation
• characterized by smoothness
• without the slightest air gap between the magnet and steel
• under perpendicular application of breakaway force (90-degree angle)
• at standard ambient temperature

Magnet lifting force in use – key factors

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

• Clearance – existence of foreign body (rust, tape, gap) acts as an insulator, which reduces capacity steeply (even by 50% at 0.5 mm).
• Loading method – catalog parameter refers to detachment vertically. When applying parallel force, the magnet holds significantly lower power (often approx. 20-30% of nominal force).
• Wall thickness – the thinner the sheet, the weaker the hold. Part of the magnetic field penetrates through instead of converting into lifting capacity.
• Material composition – different alloys reacts the same. High carbon content weaken the interaction with the magnet.
• Smoothness – full contact is obtained only on smooth steel. Rough texture create air cushions, weakening the magnet.
• Thermal conditions – NdFeB sinters have a sensitivity to temperature. At higher temperatures they are weaker, and in frost they can be stronger (up to a certain limit).

* Lifting capacity was determined using a steel plate with a smooth surface of suitable thickness (min. 20 mm), under perpendicular detachment force, however under attempts to slide the magnet the load capacity is reduced by as much as 5 times. In addition, even a small distance {between} the magnet’s surface and the plate decreases the lifting capacity.