UMP 97x40 [M8+M10] GW F300 kg / N38 - search holder

Pros and cons of NdFeB magnets.

Apart from their consistent magnetic energy, neodymium magnets have these key benefits:

• They have unchanged lifting capacity, and over around 10 years their performance decreases symbolically – ~1% (according to theory),
• Neodymium magnets are extremely resistant to demagnetization caused by magnetic disturbances,
• The use of an shiny coating of noble metals (nickel, gold, silver) causes the element to have aesthetics,
• The surface of neodymium magnets generates a unique magnetic field – this is a key feature,
• Thanks to resistance to high temperature, they are able to function (depending on the form) even at temperatures up to 230°C and higher...
• Thanks to versatility in designing and the ability to modify to individual projects,
• Huge importance in innovative solutions – they serve a role in computer drives, electric drive systems, advanced medical instruments, as well as industrial machines.
• Thanks to concentrated force, small magnets offer high operating force, with minimal size,

What to avoid - cons of neodymium magnets: weaknesses and usage proposals

• They are prone to damage upon too strong impacts. To avoid cracks, it is worth securing magnets using a steel holder. Such protection not only shields the magnet but also increases its resistance to damage
• When exposed to high temperature, neodymium magnets suffer a drop in force. 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
• 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, when using outdoors
• Limited ability of making threads in the magnet and complicated shapes - recommended is casing - mounting mechanism.
• Possible danger to health – tiny shards of magnets can be dangerous, if swallowed, which is particularly important in the aspect of protecting the youngest. It is also worth noting that small elements of these products are able to be problematic in diagnostics medical when they are in the body.
• Due to neodymium price, their price exceeds standard values,

Best holding force of the magnet in ideal parameters – what affects it?

The declared magnet strength represents the maximum value, obtained under laboratory conditions, specifically:

• on a block made of structural steel, effectively closing the magnetic flux
• with a cross-section no less than 10 mm
• with a surface perfectly flat
• with zero gap (without impurities)
• for force applied at a right angle (in the magnet axis)
• in neutral thermal conditions

Determinants of practical lifting force of a magnet

During everyday use, the actual lifting capacity depends on many variables, ranked from crucial:

• Distance (betwixt the magnet and the plate), because even a microscopic clearance (e.g. 0.5 mm) results in a reduction in force by up to 50% (this also applies to varnish, rust or dirt).
• Pull-off angle – remember that the magnet has greatest strength perpendicularly. Under shear forces, the capacity drops drastically, often to levels of 20-30% of the nominal value.
• Element thickness – for full efficiency, the steel must be adequately massive. Thin sheet limits the attraction force (the magnet "punches through" it).
• Chemical composition of the base – mild steel attracts best. Higher carbon content decrease magnetic permeability and lifting capacity.
• Plate texture – smooth surfaces ensure maximum contact, which improves force. Uneven metal reduce efficiency.
• Thermal factor – high temperature reduces pulling force. Exceeding the limit temperature can permanently damage the magnet.

* Lifting capacity testing was performed on plates with a smooth surface of optimal thickness, under perpendicular forces, in contrast under shearing force the lifting capacity is smaller. Moreover, even a slight gap {between} the magnet’s surface and the plate decreases the lifting capacity.