AM Haczyk M8 - magnetic accessories

Pros as well as cons of neodymium magnets.

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

• They retain full power for almost 10 years – the drop is just ~1% (according to analyses),
• Neodymium magnets are remarkably resistant to demagnetization caused by external field sources,
• In other words, due to the shiny layer of gold, the element gains a professional look,
• They feature high magnetic induction at the operating surface, which affects their effectiveness,
• Through (appropriate) combination of ingredients, they can achieve high thermal resistance, enabling action at temperatures reaching 230°C and above...
• Thanks to freedom in designing and the ability to customize to specific needs,
• Versatile presence in modern technologies – they find application in hard drives, brushless drives, precision medical tools, also modern systems.
• Thanks to concentrated force, small magnets offer high operating force, occupying minimum space,

Disadvantages of neodymium magnets:

• To avoid cracks upon strong impacts, we recommend using special steel holders. Such a solution protects the magnet and simultaneously improves its durability.
• When exposed to high temperature, neodymium magnets suffer a drop in power. 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 rust. Therefore during using outdoors, we advise using water-impermeable magnets made of rubber, plastic or other material protecting against moisture
• Due to limitations in producing nuts and complicated shapes in magnets, we propose using casing - magnetic holder.
• Potential hazard resulting from small fragments of magnets pose a threat, if swallowed, which gains importance in the context of child safety. It is also worth noting that small components of these magnets are able to disrupt the diagnostic process 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

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

Information about lifting capacity was determined for the most favorable conditions, including:

• using a plate made of high-permeability steel, acting as a ideal flux conductor
• with a thickness minimum 10 mm
• with an ground contact surface
• under conditions of gap-free contact (metal-to-metal)
• for force acting at a right angle (pull-off, not shear)
• at standard ambient temperature

Determinants of lifting force in real conditions

During everyday use, the actual lifting capacity is determined by a number of factors, listed from crucial:

• Space between surfaces – even a fraction of a millimeter of separation (caused e.g. by varnish or dirt) drastically reduces the magnet efficiency, often by half at just 0.5 mm.
• Angle of force application – maximum parameter is available only during perpendicular pulling. The force required to slide of the magnet along the surface is standardly many times smaller (approx. 1/5 of the lifting capacity).
• Element thickness – for full efficiency, the steel must be sufficiently thick. Paper-thin metal restricts the attraction force (the magnet "punches through" it).
• Chemical composition of the base – mild steel gives the best results. Higher carbon content decrease magnetic permeability and lifting capacity.
• Surface condition – smooth surfaces guarantee perfect abutment, which increases field saturation. Rough surfaces reduce efficiency.
• Temperature influence – hot environment weakens pulling force. Too high temperature can permanently damage the magnet.

* Lifting capacity was assessed with the use of a steel plate with a smooth surface of suitable thickness (min. 20 mm), under vertically applied force, in contrast under parallel forces the load capacity is reduced by as much as fivefold. In addition, even a minimal clearance {between} the magnet’s surface and the plate lowers the holding force.