MPL 80x40x15 / N38 - lamellar magnet

Advantages and disadvantages of neodymium magnets NdFeB.

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

• They virtually do not lose strength, because even after 10 years, the performance loss is only ~1% (according to literature),
• They remain magnetized despite exposure to magnetic surroundings,
• By applying a bright layer of silver, the element gains a clean look,
• Magnetic induction on the surface of these magnets is notably high,
• Neodymium magnets are known for very high magnetic induction and the ability to work at temperatures up to 230°C or higher (depending on the shape),
• The ability for accurate shaping or adjustment to custom needs – neodymium magnets can be manufactured in many forms and dimensions, which amplifies their functionality across industries,
• Key role in advanced technical fields – they are utilized in computer drives, electric motors, diagnostic apparatus as well as technologically developed systems,
• Relatively small size with high magnetic force – neodymium magnets offer intense magnetic field in small dimensions, which allows for use in small systems

Disadvantages of magnetic elements:

• They are prone to breaking when subjected to a strong impact. If the magnets are exposed to mechanical hits, they should be placed in a protective case. The steel housing, in the form of a holder, protects the magnet from damage and additionally reinforces its overall durability,
• They lose field intensity at increased temperatures. Most neodymium magnets experience permanent degradation in strength when heated above 80°C (depending on the shape and height). However, we offer special variants with high temperature resistance that can operate up to 230°C or higher,
• Magnets exposed to wet conditions can rust. Therefore, for outdoor applications, we recommend waterproof types made of coated materials,
• Using a cover – such as a magnetic holder – is advised due to the challenges in manufacturing threads directly in the magnet,
• Health risk linked to microscopic shards may arise, in case of ingestion, which is crucial in the protection of children. Moreover, small elements from these magnets may hinder health screening if inside the body,
• In cases of tight budgets, neodymium magnet cost may be a barrier,

Breakaway strength of the magnet in ideal conditions – what affects it?

The given holding capacity of the magnet corresponds to the highest holding force, assessed under optimal conditions, namely:

• with the use of low-carbon steel plate acting as a magnetic yoke
• with a thickness of minimum 10 mm
• with a refined outer layer
• with no separation
• in a perpendicular direction of force
• in normal thermal conditions

Practical lifting capacity: influencing factors

The lifting capacity of a magnet is determined by in practice the following factors, from primary to secondary:

• Air gap between the magnet and the plate, because even a very small distance (e.g. 0.5 mm) can cause a drop in lifting force of up to 50%.
• Direction of applied force, because the maximum lifting capacity is achieved under perpendicular application. The force required to slide the magnet along the plate is usually several times lower.
• Thickness of the plate, as a plate that is too thin causes part of the magnetic flux not to be used and to remain wasted in the air.
• Material of the plate, because higher carbon content lowers holding force, while higher iron content increases it. The best choice is steel with high magnetic permeability and high saturation induction.
• Surface of the plate, because the more smooth and polished it is, the better the contact and consequently the greater the magnetic saturation.
• Operating temperature, since all permanent magnets have a negative temperature coefficient. This means that at high temperatures they are weaker, while at sub-zero temperatures they become slightly stronger.

* Lifting capacity testing was carried out on plates with a smooth surface of optimal thickness, under perpendicular forces, whereas under parallel forces the load capacity is reduced by as much as fivefold. In addition, even a minimal clearance {between} the magnet and the plate decreases the load capacity.