MPL 40x20x10 / N38 - lamellar magnet

Advantages as well as disadvantages of NdFeB magnets.

Besides their exceptional strength, neodymium magnets offer the following advantages:

• Their power is durable, and after around 10 years it decreases only by ~1% (theoretically),
• They feature excellent resistance to magnetic field loss due to external magnetic sources,
• Thanks to the glossy finish, the plating of Ni-Cu-Ni, gold, or silver-plated gives an elegant appearance,
• The surface of neodymium magnets generates a unique magnetic field – this is a key feature,
• Through (appropriate) combination of ingredients, they can achieve high thermal resistance, enabling action at temperatures approaching 230°C and above...
• Due to the option of precise forming and adaptation to individualized needs, NdFeB magnets can be modeled in a variety of forms and dimensions, which amplifies use scope,
• Significant place in future technologies – they find application in mass storage devices, drive modules, precision medical tools, as well as technologically advanced constructions.
• Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications

Characteristics of disadvantages of neodymium magnets and ways of using them

• Brittleness is one of their disadvantages. Upon strong impact they can break. We recommend keeping them in a strong case, which not only secures them against impacts but also raises 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 force. Therefore, we recommend our special magnets marked [AH], which maintain durability even at temperatures up to 230°C
• Magnets exposed to a humid environment can corrode. Therefore while using outdoors, we recommend using waterproof magnets made of rubber, plastic or other material protecting against moisture
• Limited ability of creating threads in the magnet and complex forms - recommended is cover - mounting mechanism.
• Potential hazard related to microscopic parts of magnets pose a threat, in case of ingestion, which becomes key in the context of child safety. Furthermore, small elements of these devices can disrupt the diagnostic process medical after entering the body.
• With budget limitations the cost of neodymium magnets is economically unviable,

Maximum holding power of the magnet – what affects it?

The declared magnet strength concerns the peak performance, obtained under ideal test conditions, specifically:

• using a sheet made of high-permeability steel, functioning as a circuit closing element
• possessing a thickness of min. 10 mm to avoid saturation
• characterized by even structure
• without any air gap between the magnet and steel
• during pulling in a direction perpendicular to the plane
• at standard ambient temperature

Key elements affecting lifting force

Effective lifting capacity impacted by working environment parameters, including (from priority):

• Clearance – existence of any layer (rust, tape, gap) acts as an insulator, which reduces power rapidly (even by 50% at 0.5 mm).
• Load vector – highest force is obtained only during perpendicular pulling. The shear force of the magnet along the surface is usually several times smaller (approx. 1/5 of the lifting capacity).
• Base massiveness – insufficiently thick plate causes magnetic saturation, causing part of the flux to be lost to the other side.
• Material composition – not every steel reacts the same. High carbon content worsen the attraction effect.
• Surface finish – ideal contact is possible only on smooth steel. Any scratches and bumps reduce the real contact area, weakening the magnet.
• Operating temperature – NdFeB sinters have a negative temperature coefficient. When it is hot they are weaker, and at low temperatures they can be stronger (up to a certain limit).

* Holding force was checked on the plate surface of 20 mm thickness, when a perpendicular force was applied, however under shearing force the load capacity is reduced by as much as 5 times. Additionally, even a slight gap {between} the magnet and the plate decreases the holding force.