MPL 25x12.5x5 / N38 - lamellar magnet

Pros as well as cons of neodymium magnets.

Apart from their strong power, neodymium magnets have these key benefits:

• They have stable power, and over around ten years their performance decreases symbolically – ~1% (according to theory),
• They have excellent resistance to magnetic field loss due to opposing magnetic fields,
• In other words, due to the smooth finish of gold, the element is aesthetically pleasing,
• The surface of neodymium magnets generates a intense magnetic field – this is a distinguishing feature,
• Through (adequate) combination of ingredients, they can achieve high thermal resistance, allowing for functioning at temperatures approaching 230°C and above...
• Thanks to modularity in designing and the capacity to customize to client solutions,
• Huge importance in modern technologies – they serve a role in data components, motor assemblies, diagnostic systems, and complex engineering applications.
• Thanks to concentrated force, small magnets offer high operating force, occupying minimum space,

Disadvantages of neodymium magnets:

• They are prone to damage upon too strong impacts. To avoid cracks, it is worth protecting magnets using a steel holder. Such protection not only protects the magnet but also increases its resistance to damage
• 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 suggest using waterproof magnets made of rubber, plastic or other material stable to moisture, when using outdoors
• Limited ability of creating nuts in the magnet and complex forms - preferred is casing - magnetic holder.
• Health risk resulting from small fragments of magnets are risky, if swallowed, which becomes key in the context of child health protection. Additionally, small elements of these products can be problematic in diagnostics medical when they are in the body.
• Due to neodymium price, their price is relatively high,

Magnetic strength at its maximum – what affects it?

Breakaway force was determined for the most favorable conditions, taking into account:

• with the contact of a yoke made of low-carbon steel, ensuring maximum field concentration
• whose thickness equals approx. 10 mm
• characterized by lack of roughness
• with zero gap (no paint)
• during detachment in a direction perpendicular to the mounting surface
• in stable room temperature

Determinants of practical lifting force of a magnet

In practice, the real power results from many variables, presented from most significant:

• Gap between surfaces – even a fraction of a millimeter of separation (caused e.g. by veneer or dirt) diminishes the pulling force, often by half at just 0.5 mm.
• Angle of force application – highest force is reached only during perpendicular pulling. The shear force of the magnet along the plate is typically many times smaller (approx. 1/5 of the lifting capacity).
• Base massiveness – too thin plate does not accept the full field, causing part of the flux to be wasted into the air.
• Plate material – low-carbon steel gives the best results. Higher carbon content decrease magnetic properties and holding force.
• Base smoothness – the more even the plate, the better the adhesion and higher the lifting capacity. Roughness creates an air distance.
• Temperature influence – high temperature weakens magnetic field. Too high temperature can permanently demagnetize the magnet.

* Lifting capacity testing was conducted on a smooth plate of optimal thickness, under a perpendicular pulling force, whereas under shearing force the holding force is lower. Moreover, even a minimal clearance {between} the magnet’s surface and the plate decreases the holding force.