SM 32x425 [2xM8] / N52 - magnetic separator

Pros and cons of neodymium magnets.

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

• They virtually do not lose strength, because even after 10 years the performance loss is only ~1% (based on calculations),
• Neodymium magnets are distinguished by extremely resistant to loss of magnetic properties caused by magnetic disturbances,
• In other words, due to the shiny finish of silver, the element becomes visually attractive,
• Neodymium magnets create maximum magnetic induction on a contact point, which ensures high operational effectiveness,
• Through (appropriate) combination of ingredients, they can achieve high thermal strength, enabling action at temperatures approaching 230°C and above...
• Considering the potential of free molding and customization to specialized needs, neodymium magnets can be modeled in a variety of geometric configurations, which increases their versatility,
• Key role in innovative solutions – they serve a role in hard drives, drive modules, precision medical tools, also technologically advanced constructions.
• Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in compact dimensions, which allows their use in compact constructions

Disadvantages of neodymium magnets:

• Susceptibility to cracking is one of their disadvantages. Upon strong impact they can break. We recommend keeping them in a steel housing, which not only secures them against impacts but also increases their durability
• NdFeB magnets demagnetize when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop of power (a factor is the shape as well as dimensions of the magnet). We offer magnets specially adapted to work at temperatures up to 230°C marked [AH], which are very resistant to heat
• Due to the susceptibility of magnets to corrosion in a humid environment, we recommend using waterproof magnets made of rubber, plastic or other material immune to moisture, when using outdoors
• We suggest casing - magnetic mechanism, due to difficulties in producing threads inside the magnet and complicated forms.
• Health risk to health – tiny shards of magnets pose a threat, in case of ingestion, which gains importance in the context of child health protection. Furthermore, small components of these products can be problematic in diagnostics medical after entering the body.
• Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Breakaway strength of the magnet in ideal conditions – what it depends on?

Magnet power was defined for the most favorable conditions, including:

• using a plate made of high-permeability steel, functioning as a ideal flux conductor
• with a cross-section of at least 10 mm
• with a plane perfectly flat
• with total lack of distance (without impurities)
• during detachment in a direction perpendicular to the mounting surface
• in neutral thermal conditions

Determinants of practical lifting force of a magnet

Bear in mind that the application force may be lower depending on elements below, in order of importance:

• Distance (between the magnet and the plate), because even a very small distance (e.g. 0.5 mm) can cause a drastic drop in force by up to 50% (this also applies to varnish, corrosion or debris).
• Loading method – declared lifting capacity refers to pulling vertically. When attempting to slide, the magnet exhibits much less (often approx. 20-30% of nominal force).
• Plate thickness – too thin steel causes magnetic saturation, causing part of the power to be wasted to the other side.
• Metal type – different alloys attracts identically. Alloy additives weaken the attraction effect.
• Surface structure – the smoother and more polished the plate, the larger the contact zone and higher the lifting capacity. Unevenness creates an air distance.
• Operating temperature – NdFeB sinters have a negative temperature coefficient. When it is hot they are weaker, and in frost they can be stronger (up to a certain limit).

* Holding force was tested on a smooth steel plate of 20 mm thickness, when a perpendicular force was applied, in contrast under attempts to slide the magnet the load capacity is reduced by as much as 75%. Moreover, even a slight gap {between} the magnet’s surface and the plate reduces the holding force.