UMH 42x9x46 [M6] / N38 - magnetic holder with hook

Strengths as well as weaknesses of neodymium 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 external field influence,
• By using a decorative coating of silver, the element gains an professional look,
• They are known for high magnetic induction at the operating surface, making them more effective,
• Due to their durability and thermal resistance, neodymium magnets are capable of operate (depending on the shape) even at high temperatures reaching 230°C or more...
• Due to the ability of free forming and adaptation to unique solutions, neodymium magnets can be modeled in a variety of shapes and sizes, which amplifies use scope,
• Universal use in advanced technology sectors – they are used in HDD drives, electromotive mechanisms, medical devices, and complex engineering applications.
• Relatively small size with high pulling force – neodymium magnets offer high power in small dimensions, which enables their usage in small systems

Drawbacks and weaknesses of neodymium magnets: tips and applications.

• To avoid cracks under impact, we suggest using special steel holders. Such a solution secures the magnet and simultaneously improves its durability.
• When exposed to high temperature, neodymium magnets experience a drop in power. Often, when the temperature exceeds 80°C, their power 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 rust. Therefore while using outdoors, we suggest using water-impermeable magnets made of rubber, plastic or other material protecting against moisture
• Limited possibility of producing threads in the magnet and complex forms - preferred is a housing - magnetic holder.
• Health risk to health – tiny shards of magnets can be dangerous, if swallowed, which becomes key in the aspect of protecting the youngest. Furthermore, tiny parts of these products are able to complicate diagnosis medical after entering the body.
• With large orders the cost of neodymium magnets is a challenge,

Highest magnetic holding force – what affects it?

Breakaway force was defined for the most favorable conditions, taking into account:

• on a block made of mild steel, effectively closing the magnetic flux
• possessing a thickness of min. 10 mm to avoid saturation
• characterized by lack of roughness
• under conditions of gap-free contact (metal-to-metal)
• for force acting at a right angle (in the magnet axis)
• at standard ambient temperature

Lifting capacity in practice – influencing factors

It is worth knowing that the magnet holding may be lower depending on the following factors, in order of importance:

• Air gap (between the magnet and the plate), since even a tiny distance (e.g. 0.5 mm) results in a reduction in force by up to 50% (this also applies to paint, rust or debris).
• Loading method – catalog parameter refers to pulling vertically. When attempting to slide, the magnet holds significantly lower power (often approx. 20-30% of nominal force).
• Wall thickness – thin material does not allow full use of the magnet. Magnetic flux penetrates through instead of converting into lifting capacity.
• Metal type – different alloys reacts the same. Alloy additives weaken the attraction effect.
• Surface condition – smooth surfaces guarantee perfect abutment, which improves field saturation. Rough surfaces reduce efficiency.
• Operating temperature – neodymium magnets have a sensitivity to temperature. When it is hot they are weaker, and in frost they can be stronger (up to a certain limit).

* Lifting capacity was assessed using a smooth steel plate of suitable thickness (min. 20 mm), under perpendicular pulling force, whereas under shearing force the load capacity is reduced by as much as 5 times. Moreover, even a minimal clearance {between} the magnet and the plate lowers the holding force.