UMH 48x11x65 [M6] / N38 - magnetic holder with hook

Strengths as well as weaknesses of NdFeB magnets.

In addition to their magnetic capacity, neodymium magnets provide the following advantages:

• They have unchanged lifting capacity, and over nearly ten years their performance decreases symbolically – ~1% (according to theory),
• They feature excellent resistance to weakening of magnetic properties due to opposing magnetic fields,
• Thanks to the glossy finish, the surface of Ni-Cu-Ni, gold, or silver gives an visually attractive appearance,
• Magnets possess exceptionally strong magnetic induction on the outer side,
• Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their form) at temperatures up to 230°C and above...
• Thanks to the ability of precise shaping and customization to unique needs, magnetic components can be created in a variety of shapes and sizes, which makes them more universal,
• Versatile presence in future technologies – they are used in computer drives, brushless drives, advanced medical instruments, as well as other advanced devices.
• Thanks to concentrated force, small magnets offer high operating force, occupying minimum space,

Disadvantages of NdFeB magnets:

• Brittleness is one of their disadvantages. Upon intense impact they can fracture. We advise keeping them in a steel housing, which not only secures them against impacts but also raises their durability
• When exposed to high temperature, neodymium magnets experience a drop in strength. Often, when the temperature exceeds 80°C, their strength decreases (depending on the size and shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding 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 resistant to moisture
• Due to limitations in realizing nuts and complex forms in magnets, we propose using a housing - magnetic mount.
• Potential hazard resulting from small fragments of magnets can be dangerous, if swallowed, which becomes key in the context of child health protection. Additionally, small components of these magnets can disrupt the diagnostic process medical after entering the body.
• Due to neodymium price, their price exceeds standard values,

Maximum holding power of the magnet – what it depends on?

The specified lifting capacity concerns the peak performance, recorded under ideal test conditions, meaning:

• on a base made of mild steel, perfectly concentrating the magnetic flux
• with a cross-section minimum 10 mm
• with a plane free of scratches
• with total lack of distance (without coatings)
• for force acting at a right angle (in the magnet axis)
• at standard ambient temperature

Determinants of practical lifting force of a magnet

Holding efficiency is influenced by specific conditions, mainly (from most important):

• Distance – the presence of any layer (rust, tape, air) acts as an insulator, which lowers power rapidly (even by 50% at 0.5 mm).
• Force direction – remember that the magnet holds strongest perpendicularly. Under shear forces, the holding force drops drastically, often to levels of 20-30% of the maximum value.
• Substrate thickness – for full efficiency, the steel must be sufficiently thick. Paper-thin metal restricts the lifting capacity (the magnet "punches through" it).
• Material composition – not every steel reacts the same. High carbon content weaken the interaction with the magnet.
• Surface condition – ground elements ensure maximum contact, which increases field saturation. Rough surfaces weaken the grip.
• Thermal environment – heating the magnet results in weakening of induction. Check the maximum operating temperature for a given model.

* Lifting capacity was measured by applying a polished steel plate of optimal thickness (min. 20 mm), under perpendicular detachment force, however under attempts to slide the magnet the holding force is lower. In addition, even a slight gap {between} the magnet’s surface and the plate lowers the load capacity.