SM 18x100 [2xM5] / N42 - magnetic separator

Pros and cons of rare earth magnets.

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

• They virtually do not lose strength, because even after 10 years the decline in efficiency is only ~1% (in laboratory conditions),
• They do not lose their magnetic properties even under close interference source,
• In other words, due to the smooth layer of silver, the element gains a professional look,
• The surface of neodymium magnets generates a maximum magnetic field – this is a distinguishing feature,
• Through (adequate) combination of ingredients, they can achieve high thermal resistance, enabling functioning at temperatures reaching 230°C and above...
• Thanks to versatility in forming and the capacity to customize to individual projects,
• Versatile presence in electronics industry – they are commonly used in data components, electromotive mechanisms, diagnostic systems, as well as multitasking production systems.
• Thanks to their power density, small magnets offer high operating force, with minimal size,

What to avoid - cons of neodymium magnets: application proposals

• Brittleness is one of their disadvantages. Upon intense impact they can break. We recommend keeping them in a special holder, which not only protects them against impacts but also increases their durability
• Neodymium magnets decrease their strength under the influence of heating. As soon as 80°C is exceeded, many of them start losing their force. Therefore, we recommend our special magnets marked [AH], which maintain durability even at temperatures up to 230°C
• They rust in a humid environment. For use outdoors we recommend using waterproof magnets e.g. in rubber, plastic
• Due to limitations in creating threads and complicated forms in magnets, we recommend using casing - magnetic mount.
• Potential hazard resulting from small fragments of magnets are risky, in case of ingestion, which is particularly important in the aspect of protecting the youngest. Additionally, small components of these products can complicate diagnosis medical after entering the body.
• High unit price – neodymium magnets are more expensive than other types of magnets (e.g. ferrite), which increases costs of application in large quantities

Breakaway strength of the magnet in ideal conditions – what contributes to it?

Breakaway force was determined for the most favorable conditions, assuming:

• with the use of a yoke made of special test steel, guaranteeing maximum field concentration
• possessing a massiveness of minimum 10 mm to avoid saturation
• with a surface perfectly flat
• with total lack of distance (without paint)
• during pulling in a direction vertical to the plane
• at ambient temperature room level

Lifting capacity in practice – influencing factors

Effective lifting capacity is affected by working environment parameters, such as (from priority):

• Clearance – existence of any layer (rust, tape, air) acts as an insulator, which lowers capacity steeply (even by 50% at 0.5 mm).
• Force direction – declared lifting capacity refers to pulling vertically. When applying parallel force, the magnet exhibits much less (typically approx. 20-30% of nominal force).
• Base massiveness – too thin plate causes magnetic saturation, causing part of the flux to be escaped into the air.
• Steel type – mild steel attracts best. Alloy admixtures decrease magnetic permeability and lifting capacity.
• Surface quality – the more even the plate, the better the adhesion and higher the lifting capacity. Unevenness acts like micro-gaps.
• Thermal environment – temperature increase results in weakening of force. Check the thermal limit for a given model.

* Lifting capacity was determined using a polished steel plate of optimal thickness (min. 20 mm), under vertically applied force, whereas under shearing force the holding force is lower. Moreover, even a slight gap {between} the magnet’s surface and the plate decreases the holding force.