BM 450x180x70 [4x M8] - magnetic beam

Advantages as well as disadvantages of neodymium magnets.

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

• They retain full power for around 10 years – the drop is just ~1% (based on simulations),
• Neodymium magnets prove to be extremely resistant to loss of magnetic properties caused by magnetic disturbances,
• A magnet with a shiny nickel surface is more attractive,
• Magnets are characterized by extremely high magnetic induction on the outer layer,
• Through (adequate) combination of ingredients, they can achieve high thermal strength, allowing for operation at temperatures reaching 230°C and above...
• Due to the potential of precise molding and adaptation to unique projects, neodymium magnets can be created in a variety of forms and dimensions, which amplifies use scope,
• Huge importance in modern industrial fields – they are used in HDD drives, electric motors, medical equipment, and modern systems.
• Compactness – despite small sizes they provide effective action, making them ideal for precision applications

Cons of neodymium magnets: tips and applications.

• To avoid cracks under impact, we recommend using special steel holders. Such a solution secures the magnet and simultaneously increases its durability.
• Neodymium magnets decrease their strength 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
• Due to the susceptibility of magnets to corrosion in a humid environment, we advise using waterproof magnets made of rubber, plastic or other material resistant to moisture, in case of application outdoors
• Due to limitations in realizing threads and complex shapes in magnets, we propose using a housing - magnetic mount.
• Possible danger resulting from small fragments of magnets can be dangerous, when accidentally swallowed, which gains importance in the aspect of protecting the youngest. Furthermore, small components of these magnets are able to disrupt the diagnostic process medical after entering the body.
• Due to expensive raw materials, their price is relatively high,

Highest magnetic holding force – what it depends on?

Magnet power was defined for optimal configuration, including:

• using a plate made of high-permeability steel, functioning as a circuit closing element
• whose transverse dimension equals approx. 10 mm
• characterized by even structure
• without the slightest insulating layer between the magnet and steel
• for force applied at a right angle (pull-off, not shear)
• in neutral thermal conditions

Magnet lifting force in use – key factors

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

• Clearance – the presence of foreign body (rust, dirt, gap) interrupts the magnetic circuit, which lowers power rapidly (even by 50% at 0.5 mm).
• Force direction – note that the magnet holds strongest perpendicularly. Under shear forces, the capacity drops significantly, often to levels of 20-30% of the maximum value.
• Metal thickness – the thinner the sheet, the weaker the hold. Part of the magnetic field passes through the material instead of converting into lifting capacity.
• Chemical composition of the base – mild steel gives the best results. Alloy steels reduce magnetic properties and holding force.
• Surface finish – full contact is possible only on polished steel. Any scratches and bumps create air cushions, weakening the magnet.
• Thermal factor – high temperature weakens pulling force. Exceeding the limit temperature can permanently demagnetize the magnet.

* Lifting capacity was measured using a steel plate with a smooth surface of suitable thickness (min. 20 mm), under perpendicular pulling force, in contrast under shearing force the load capacity is reduced by as much as fivefold. Additionally, even a small distance {between} the magnet’s surface and the plate decreases the holding force.