HH 42x8.8 [M6] / N38 - through hole magnetic holder

Pros and cons of neodymium magnets.

Besides their durability, neodymium magnets are valued for these benefits:

• They have unchanged lifting capacity, and over more than ten years their performance decreases symbolically – ~1% (in testing),
• They retain their magnetic properties even under external field action,
• Thanks to the metallic finish, the layer of nickel, gold, or silver-plated gives an aesthetic appearance,
• They show high magnetic induction at the operating surface, which improves attraction properties,
• Due to their durability and thermal resistance, neodymium magnets can operate (depending on the shape) even at high temperatures reaching 230°C or more...
• Due to the option of free shaping and customization to specialized projects, NdFeB magnets can be manufactured in a broad palette of forms and dimensions, which expands the range of possible applications,
• Fundamental importance in modern technologies – they are utilized in data components, electric drive systems, advanced medical instruments, as well as multitasking production systems.
• Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in tiny dimensions, which makes them useful in compact constructions

Disadvantages of neodymium magnets:

• Susceptibility to cracking is one of their disadvantages. Upon intense impact they can fracture. We advise keeping them in a special holder, which not only protects them against impacts but also increases their durability
• When exposed to high temperature, neodymium magnets experience a drop in power. Often, when the temperature exceeds 80°C, their strength 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
• Due to the susceptibility of magnets to corrosion in a humid environment, we recommend using waterproof magnets made of rubber, plastic or other material immune to moisture, when using outdoors
• Due to limitations in producing nuts and complex shapes in magnets, we recommend using cover - magnetic mechanism.
• Possible danger related to microscopic parts of magnets are risky, in case of ingestion, which is particularly important in the context of child safety. It is also worth noting that small components of these products can complicate diagnosis medical when they are in the body.
• Due to expensive raw materials, their price exceeds standard values,

Optimal lifting capacity of a neodymium magnet – what affects it?

Magnet power was determined for ideal contact conditions, including:

• using a plate made of low-carbon steel, acting as a magnetic yoke
• whose transverse dimension equals approx. 10 mm
• with an ground contact surface
• under conditions of gap-free contact (surface-to-surface)
• for force acting at a right angle (in the magnet axis)
• in stable room temperature

Lifting capacity in practice – influencing factors

Please note that the application force may be lower depending on elements below, starting with the most relevant:

• Clearance – existence of foreign body (paint, dirt, air) interrupts the magnetic circuit, which lowers power rapidly (even by 50% at 0.5 mm).
• Pull-off angle – note that the magnet holds strongest perpendicularly. Under sliding down, the capacity drops significantly, often to levels of 20-30% of the nominal value.
• Substrate thickness – to utilize 100% power, the steel must be sufficiently thick. Thin sheet restricts the attraction force (the magnet "punches through" it).
• Material composition – different alloys attracts identically. Alloy additives worsen the interaction with the magnet.
• Surface condition – ground elements ensure maximum contact, which increases field saturation. Uneven metal reduce efficiency.
• Operating temperature – NdFeB sinters have a negative temperature coefficient. At higher temperatures they lose power, and in frost they can be stronger (up to a certain limit).

* Lifting capacity was determined by applying a steel plate with a smooth surface of suitable thickness (min. 20 mm), under perpendicular pulling force, in contrast under parallel forces the holding force is lower. In addition, even a minimal clearance {between} the magnet and the plate decreases the holding force.