SM 32x425 [2xM8] / N52 - magnetic separator

Pros and cons of NdFeB magnets.

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

• Their magnetic field is maintained, and after approximately 10 years it decreases only by ~1% (according to research),
• Neodymium magnets remain extremely resistant to loss of magnetic properties caused by external magnetic fields,
• Thanks to the elegant finish, the coating of nickel, gold, or silver-plated gives an elegant appearance,
• Neodymium magnets ensure maximum magnetic induction on a small area, which allows for strong attraction,
• Due to their durability and thermal resistance, neodymium magnets are capable of operate (depending on the shape) even at high temperatures reaching 230°C or more...
• Thanks to the option of flexible forming and customization to specialized needs, magnetic components can be produced in a variety of shapes and sizes, which amplifies use scope,
• Universal use in modern industrial fields – they are used in hard drives, motor assemblies, medical devices, as well as multitasking production systems.
• Thanks to concentrated force, small magnets offer high operating force, in miniature format,

Disadvantages of neodymium magnets:

• Brittleness is one of their disadvantages. Upon intense impact they can fracture. We advise keeping them in a strong case, which not only secures them against impacts but also increases their durability
• Neodymium magnets lose their power under the influence of heating. As soon as 80°C is exceeded, many of them start losing their power. Therefore, we recommend our special magnets marked [AH], which maintain stability even at temperatures up to 230°C
• When exposed to humidity, magnets start to rust. For applications outside, it is recommended to use protective magnets, such as magnets in rubber or plastics, which prevent oxidation and corrosion.
• We suggest cover - magnetic holder, due to difficulties in creating nuts inside the magnet and complex forms.
• Potential hazard related to microscopic parts of magnets pose a threat, when accidentally swallowed, which gains importance in the context of child health protection. It is also worth noting that tiny parts of these products can disrupt the diagnostic process medical when they are in the body.
• High unit price – neodymium magnets are more expensive than other types of magnets (e.g. ferrite), which increases costs of application in large quantities

Maximum lifting capacity of the magnet – what affects it?

Information about lifting capacity is the result of a measurement for ideal contact conditions, including:

• with the contact of a sheet made of special test steel, ensuring full magnetic saturation
• possessing a thickness of min. 10 mm to avoid saturation
• characterized by smoothness
• without any air gap between the magnet and steel
• under perpendicular force vector (90-degree angle)
• at room temperature

Practical lifting capacity: influencing factors

Holding efficiency impacted by specific conditions, such as (from most important):

• Air gap (betwixt the magnet and the metal), as even a very small clearance (e.g. 0.5 mm) results in a reduction in force by up to 50% (this also applies to paint, rust or debris).
• Pull-off angle – remember that the magnet holds strongest perpendicularly. Under shear forces, the holding force drops drastically, often to levels of 20-30% of the maximum value.
• Substrate thickness – to utilize 100% power, the steel must be adequately massive. Paper-thin metal restricts the lifting capacity (the magnet "punches through" it).
• Material type – ideal substrate is high-permeability steel. Stainless steels may attract less.
• Surface condition – smooth surfaces ensure maximum contact, which increases force. Uneven metal reduce efficiency.
• Heat – neodymium magnets have a negative temperature coefficient. At higher temperatures they are weaker, and at low temperatures they can be stronger (up to a certain limit).

* Lifting capacity was determined by applying a polished steel plate of optimal thickness (min. 20 mm), under vertically applied force, however under attempts to slide the magnet the load capacity is reduced by as much as 75%. In addition, even a slight gap {between} the magnet and the plate reduces the load capacity.