UMGB 107x40 [M8+M10] GW F400 +Lina GOBLIN / N38 - goblin magnetic holder

Strengths and weaknesses of NdFeB magnets.

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

• They virtually do not lose power, because even after 10 years the decline in efficiency is only ~1% (based on calculations),
• They show high resistance to demagnetization induced by presence of other magnetic fields,
• By using a smooth layer of silver, the element presents an modern look,
• Magnetic induction on the working layer of the magnet is maximum,
• Through (adequate) combination of ingredients, they can achieve high thermal resistance, allowing for functioning at temperatures reaching 230°C and above...
• Due to the potential of accurate molding and customization to specialized solutions, NdFeB magnets can be modeled in a variety of forms and dimensions, which increases their versatility,
• Universal use in future technologies – they find application in computer drives, drive modules, medical devices, and technologically advanced constructions.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

Disadvantages of NdFeB magnets:

• To avoid cracks under impact, we recommend using special steel holders. Such a solution secures the magnet and simultaneously improves its durability.
• We warn that neodymium magnets can lose their strength at high temperatures. To prevent this, we recommend our specialized [AH] magnets, which work effectively even at 230°C.
• Magnets exposed to a humid environment can rust. Therefore when using outdoors, we suggest using waterproof magnets made of rubber, plastic or other material protecting against moisture
• Limited ability of making nuts in the magnet and complex shapes - preferred is cover - magnetic holder.
• Potential hazard related to microscopic parts of magnets can be dangerous, if swallowed, which becomes key in the context of child health protection. It is also worth noting that tiny parts of these products are able to complicate diagnosis medical when they are in the body.
• With budget limitations the cost of neodymium magnets is economically unviable,

Maximum lifting capacity of the magnet – what it depends on?

Holding force of 480 kg is a theoretical maximum value conducted under the following configuration:

• with the contact of a yoke made of low-carbon steel, ensuring full magnetic saturation
• possessing a massiveness of min. 10 mm to ensure full flux closure
• characterized by even structure
• without any clearance between the magnet and steel
• for force applied at a right angle (pull-off, not shear)
• at temperature room level

Practical aspects of lifting capacity – factors

Effective lifting capacity is affected by specific conditions, such as (from priority):

• Gap between surfaces – even a fraction of a millimeter of distance (caused e.g. by varnish or unevenness) diminishes the magnet efficiency, often by half at just 0.5 mm.
• Pull-off angle – note that the magnet has greatest strength perpendicularly. Under sliding down, the holding force drops drastically, often to levels of 20-30% of the maximum value.
• Metal thickness – the thinner the sheet, the weaker the hold. Magnetic flux passes through the material instead of converting into lifting capacity.
• Plate material – mild steel attracts best. Higher carbon content decrease magnetic permeability and lifting capacity.
• Plate texture – smooth surfaces guarantee perfect abutment, which increases field saturation. Uneven metal reduce efficiency.
• Temperature – heating the magnet causes a temporary drop of induction. Check the thermal limit for a given model.

* Holding force was tested on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, whereas under shearing force the holding force is lower. Additionally, even a slight gap {between} the magnet and the plate decreases the lifting capacity.