HH 16x5.3 [M3] / N38 - through hole magnetic holder

Advantages and disadvantages of rare earth magnets.

In addition to their pulling strength, neodymium magnets provide the following advantages:

• They retain attractive force for around ten years – the drop is just ~1% (according to analyses),
• They retain their magnetic properties even under close interference source,
• In other words, due to the glossy layer of gold, the element is aesthetically pleasing,
• Magnets exhibit excellent magnetic induction on the active area,
• Due to their durability and thermal resistance, neodymium magnets can operate (depending on the form) even at high temperatures reaching 230°C or more...
• Thanks to flexibility in forming and the ability to modify to individual projects,
• Universal use in future technologies – they find application in mass storage devices, drive modules, precision medical tools, as well as complex engineering applications.
• Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications

What to avoid - cons of neodymium magnets and proposals for their use:

• At very strong impacts they can break, therefore we advise placing them in strong housings. A metal housing provides additional protection against damage and increases the magnet's durability.
• We warn that neodymium magnets can reduce their power at high temperatures. To prevent this, we advise our specialized [AH] magnets, which work effectively even at 230°C.
• Magnets exposed to a humid environment can corrode. Therefore during using outdoors, we suggest using waterproof magnets made of rubber, plastic or other material protecting against moisture
• Limited ability of creating threads in the magnet and complicated forms - recommended is a housing - mounting mechanism.
• Potential hazard to health – tiny shards of magnets pose a threat, when accidentally swallowed, which is particularly important in the aspect of protecting the youngest. Furthermore, tiny parts of these magnets are able to complicate diagnosis medical after entering the body.
• High unit price – neodymium magnets are more expensive than other types of magnets (e.g. ferrite), which can limit application in large quantities

Magnetic strength at its maximum – what it depends on?

Breakaway force is the result of a measurement for ideal contact conditions, including:

• using a sheet made of low-carbon steel, acting as a magnetic yoke
• with a cross-section no less than 10 mm
• with an ground touching surface
• with zero gap (without coatings)
• under axial force vector (90-degree angle)
• at temperature room level

Practical aspects of lifting capacity – factors

In real-world applications, the actual holding force depends on several key aspects, presented from crucial:

• Space between surfaces – every millimeter of separation (caused e.g. by veneer or dirt) significantly weakens the pulling force, often by half at just 0.5 mm.
• Angle of force application – highest force is reached only during perpendicular pulling. The shear force of the magnet along the plate is standardly several times lower (approx. 1/5 of the lifting capacity).
• Plate thickness – too thin steel does not close the flux, causing part of the power to be escaped to the other side.
• Metal type – different alloys reacts the same. High carbon content weaken the attraction effect.
• Surface quality – the more even the surface, the larger the contact zone and stronger the hold. Unevenness acts like micro-gaps.
• Temperature – temperature increase causes a temporary drop of induction. Check the maximum operating temperature for a given model.

* Lifting capacity testing was conducted on a smooth plate of suitable thickness, under perpendicular forces, however under attempts to slide the magnet the load capacity is reduced by as much as 5 times. Additionally, even a minimal clearance {between} the magnet’s surface and the plate lowers the load capacity.