UMGGW 34x8 [M4] GW / N38 - magnetic holder rubber internal thread

Strengths and weaknesses of NdFeB magnets.

Apart from their superior magnetism, neodymium magnets have these key benefits:

• They have constant strength, and over around 10 years their attraction force decreases symbolically – ~1% (in testing),
• They do not lose their magnetic properties even under external field action,
• Thanks to the shimmering finish, the layer of nickel, gold, or silver-plated gives an professional appearance,
• Neodymium magnets achieve maximum magnetic induction on a small area, which allows for strong attraction,
• Through (adequate) combination of ingredients, they can achieve high thermal resistance, enabling action at temperatures approaching 230°C and above...
• In view of the potential of free molding and customization to specialized requirements, neodymium magnets can be produced in a variety of geometric configurations, which amplifies use scope,
• Fundamental importance in innovative solutions – they serve a role in hard drives, motor assemblies, diagnostic systems, also technologically advanced constructions.
• Relatively small size with high pulling force – neodymium magnets offer high power in tiny dimensions, which enables their usage in compact constructions

Disadvantages of neodymium magnets:

• They are prone to damage upon too strong impacts. To avoid cracks, it is worth securing magnets in a protective case. Such protection not only protects the magnet but also increases its resistance to damage
• We warn that neodymium magnets can reduce their power at high temperatures. To prevent this, we recommend our specialized [AH] magnets, which work effectively even at 230°C.
• They oxidize in a humid environment. For use outdoors we recommend using waterproof magnets e.g. in rubber, plastic
• Limited possibility of making threads in the magnet and complex forms - recommended is casing - magnetic holder.
• Health risk resulting from small fragments of magnets are risky, when accidentally swallowed, which gains importance in the context of child health protection. It is also worth noting that small components of these magnets can disrupt the diagnostic process medical when they are in the body.
• With large orders the cost of neodymium magnets is economically unviable,

Magnetic strength at its maximum – what affects it?

The force parameter is a theoretical maximum value executed under the following configuration:

• on a plate made of structural steel, optimally conducting the magnetic flux
• possessing a thickness of minimum 10 mm to ensure full flux closure
• with an ground touching surface
• with zero gap (no coatings)
• for force acting at a right angle (in the magnet axis)
• at temperature approx. 20 degrees Celsius

Practical lifting capacity: influencing factors

Holding efficiency is affected by specific conditions, mainly (from priority):

• Gap (between the magnet and the plate), as even a tiny clearance (e.g. 0.5 mm) results in a decrease in force by up to 50% (this also applies to paint, rust or dirt).
• Load vector – highest force is obtained only during perpendicular pulling. The shear force of the magnet along the surface is typically several times smaller (approx. 1/5 of the lifting capacity).
• Steel thickness – insufficiently thick plate causes magnetic saturation, causing part of the flux to be lost into the air.
• Material composition – different alloys attracts identically. High carbon content weaken the attraction effect.
• Surface condition – ground elements guarantee perfect abutment, which increases force. Rough surfaces reduce efficiency.
• Operating temperature – neodymium magnets 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).

* Lifting capacity testing was conducted on a smooth plate of suitable thickness, under perpendicular forces, however under parallel forces the holding force is lower. Moreover, even a minimal clearance {between} the magnet’s surface and the plate lowers the lifting capacity.