UMS 16x6.5x3.5x5 / N38 - conical magnetic holder

Pros and cons of neodymium magnets.

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

• They do not lose strength, even over approximately 10 years – the decrease in lifting capacity is only ~1% (based on measurements),
• They maintain their magnetic properties even under close interference source,
• In other words, due to the smooth surface of nickel, the element gains a professional look,
• They are known for high magnetic induction at the operating surface, making them more effective,
• Through (appropriate) combination of ingredients, they can achieve high thermal resistance, enabling operation at temperatures reaching 230°C and above...
• Possibility of exact shaping as well as modifying to defined applications,
• Key role in innovative solutions – they serve a role in magnetic memories, electric drive systems, medical equipment, also industrial machines.
• Thanks to efficiency per cm³, small magnets offer high operating force, occupying minimum space,

Problematic aspects of neodymium magnets and proposals for their use:

• At strong impacts they can crack, therefore we recommend placing them in special holders. A metal housing provides additional protection against damage, as well as increases the magnet's durability.
• We warn that neodymium magnets can reduce their power at high temperatures. To prevent this, we recommend our specialized [AH] magnets, which work effectively even at 230°C.
• When exposed to humidity, magnets start to rust. To use them in conditions outside, it is recommended to use protective magnets, such as those in rubber or plastics, which prevent oxidation as well as corrosion.
• Limited ability of producing nuts in the magnet and complicated forms - recommended is a housing - magnet mounting.
• Potential hazard related to microscopic parts of magnets can be dangerous, when accidentally swallowed, which is particularly important in the context of child safety. Furthermore, small elements of these products are able to be problematic in diagnostics medical when they are in the body.
• Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Detachment force of the magnet in optimal conditions – what contributes to it?

The load parameter shown concerns the peak performance, measured under optimal environment, specifically:

• using a plate made of high-permeability steel, functioning as a ideal flux conductor
• with a thickness minimum 10 mm
• with a plane perfectly flat
• with zero gap (without coatings)
• under axial application of breakaway force (90-degree angle)
• in stable room temperature

Key elements affecting lifting force

Please note that the working load may be lower subject to the following factors, starting with the most relevant:

• Space between surfaces – every millimeter of distance (caused e.g. by veneer or unevenness) significantly weakens the pulling force, often by half at just 0.5 mm.
• Force direction – catalog parameter refers to detachment vertically. When applying parallel force, the magnet holds much less (typically approx. 20-30% of maximum force).
• Metal thickness – the thinner the sheet, the weaker the hold. Magnetic flux penetrates through instead of converting into lifting capacity.
• Metal type – different alloys reacts the same. High carbon content weaken the attraction effect.
• Plate texture – smooth surfaces ensure maximum contact, which improves field saturation. Rough surfaces weaken the grip.
• Temperature – temperature increase causes a temporary drop of induction. Check the thermal limit for a given model.

* Holding force was tested on the plate surface of 20 mm thickness, when a perpendicular force was applied, in contrast under attempts to slide the magnet the holding force is lower. Moreover, even a small distance {between} the magnet’s surface and the plate lowers the load capacity.