SMZR 32x100 / N52 - magnetic separator with handle

Pros and cons of neodymium magnets.

Besides their remarkable strength, neodymium magnets offer the following advantages:

• They have unchanged lifting capacity, and over nearly ten years their performance decreases symbolically – ~1% (according to theory),
• They retain their magnetic properties even under external field action,
• The use of an metallic coating of noble metals (nickel, gold, silver) causes the element to have aesthetics,
• Neodymium magnets deliver maximum magnetic induction on a contact point, which allows for strong attraction,
• Due to their durability and thermal resistance, neodymium magnets can operate (depending on the form) even at high temperatures reaching 230°C or more...
• In view of the ability of precise molding and customization to custom solutions, NdFeB magnets can be manufactured in a variety of geometric configurations, which amplifies use scope,
• Versatile presence in innovative solutions – they serve a role in data components, brushless drives, medical equipment, also complex engineering applications.
• Thanks to efficiency per cm³, small magnets offer high operating force, in miniature format,

Cons of neodymium magnets and proposals for their use:

• Brittleness is one of their disadvantages. Upon strong impact they can fracture. We recommend keeping them in a strong case, which not only secures them against impacts but also increases their durability
• We warn that neodymium magnets can lose their strength at high temperatures. To prevent this, we suggest our specialized [AH] magnets, which work effectively even at 230°C.
• Due to the susceptibility of magnets to corrosion in a humid environment, we suggest using waterproof magnets made of rubber, plastic or other material stable to moisture, when using outdoors
• Due to limitations in creating nuts and complex shapes in magnets, we propose using cover - magnetic mechanism.
• Health risk resulting from small fragments of magnets are risky, when accidentally swallowed, which becomes key in the aspect of protecting the youngest. It is also worth noting that tiny parts of these magnets can complicate diagnosis medical when they are in the body.
• Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

Highest magnetic holding force – what it depends on?

The declared magnet strength represents the maximum value, recorded under laboratory conditions, specifically:

• with the use of a yoke made of low-carbon steel, guaranteeing maximum field concentration
• with a thickness of at least 10 mm
• characterized by smoothness
• without any clearance between the magnet and steel
• for force acting at a right angle (in the magnet axis)
• at room temperature

Determinants of lifting force in real conditions

Please note that the magnet holding will differ depending on elements below, in order of importance:

• Gap between magnet and steel – every millimeter of distance (caused e.g. by varnish or dirt) drastically reduces the pulling force, often by half at just 0.5 mm.
• Angle of force application – maximum parameter is available only during pulling at a 90° angle. The resistance to sliding of the magnet along the surface is standardly several times lower (approx. 1/5 of the lifting capacity).
• Element thickness – to utilize 100% power, the steel must be adequately massive. Paper-thin metal limits the lifting capacity (the magnet "punches through" it).
• Chemical composition of the base – mild steel gives the best results. Higher carbon content reduce magnetic permeability and holding force.
• Surface condition – ground elements ensure maximum contact, which improves field saturation. Uneven metal reduce efficiency.
• Thermal environment – temperature increase causes a temporary drop of force. Check the maximum operating temperature for a given model.

* Lifting capacity testing was performed on plates with a smooth surface of suitable thickness, under perpendicular forces, however under parallel forces the lifting capacity is smaller. Moreover, even a minimal clearance {between} the magnet and the plate reduces the holding force.