NC NeoCube fi 5 mm kuleczki kolorowe / N38 - neocube

Strengths and weaknesses of NdFeB magnets.

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

• They retain attractive force for around 10 years – the loss is just ~1% (according to analyses),
• Neodymium magnets are extremely resistant to demagnetization caused by external magnetic fields,
• The use of an refined coating of noble metals (nickel, gold, silver) causes the element to present itself better,
• They are known for high magnetic induction at the operating surface, which increases their power,
• Through (appropriate) combination of ingredients, they can achieve high thermal resistance, allowing for action at temperatures reaching 230°C and above...
• Thanks to flexibility in designing and the capacity to modify to individual projects,
• Universal use in high-tech industry – they are commonly used in magnetic memories, drive modules, diagnostic systems, and modern systems.
• Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in compact dimensions, which enables their usage in miniature devices

Problematic aspects of neodymium magnets: application proposals

• They are prone to damage upon too strong impacts. To avoid cracks, it is worth securing magnets using a steel holder. Such protection not only protects the magnet but also increases its resistance to damage
• Neodymium magnets lose 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 stability even at temperatures up to 230°C
• They oxidize in a humid environment. For use outdoors we advise using waterproof magnets e.g. in rubber, plastic
• Due to limitations in creating threads and complex shapes in magnets, we propose using a housing - magnetic mechanism.
• Potential hazard resulting from small fragments of magnets are risky, in case of ingestion, which becomes key in the context of child health protection. Additionally, small elements of these magnets can be problematic in diagnostics medical in case of swallowing.
• With budget limitations the cost of neodymium magnets can be a barrier,

Magnetic strength at its maximum – what it depends on?

Information about lifting capacity was defined for ideal contact conditions, including:

• using a sheet made of mild steel, functioning as a circuit closing element
• with a thickness no less than 10 mm
• with an polished contact surface
• with zero gap (no impurities)
• under perpendicular force vector (90-degree angle)
• at ambient temperature room level

Practical aspects of lifting capacity – factors

Bear in mind that the application force will differ subject to elements below, starting with the most relevant:

• Gap between magnet and steel – even a fraction of a millimeter of separation (caused e.g. by varnish or unevenness) diminishes the magnet efficiency, often by half at just 0.5 mm.
• Pull-off angle – note that the magnet holds strongest perpendicularly. Under sliding down, the holding force drops drastically, often to levels of 20-30% of the nominal value.
• Substrate thickness – for full efficiency, the steel must be adequately massive. Thin sheet restricts the attraction force (the magnet "punches through" it).
• Material type – ideal substrate is pure iron steel. Stainless steels may attract less.
• Surface structure – the more even the plate, the larger the contact zone and higher the lifting capacity. Unevenness creates an air distance.
• Temperature influence – high temperature reduces magnetic field. Too high temperature can permanently demagnetize the magnet.

* Lifting capacity was measured by applying a smooth steel plate of optimal thickness (min. 20 mm), under perpendicular pulling force, however under attempts to slide the magnet the lifting capacity is smaller. Additionally, even a slight gap {between} the magnet and the plate reduces the load capacity.