Neodymium Block Magnets

Product Information

Rare Earth block rectangle magnets (Neodymium) are among the most powerful permanent magnets available. Our range is suited to a wide range of applications, including magnetic separators in the food industry, flow control systems and water conditioning to name but a few. The multi-purpose Rare Earth blocks are the number one magnet of choice due to the power of today’s magnetic alloys. Our neodymium block magnets, also called rare earth block magnets, are offered in several sizes, shapes and grades. They are the best alternative if you require a multipurpose magnet with maximum magnetic strength.

Neodymium blocks are used in many different industries such as design, advertising, engineering, manufacturing, printing, film, science, construction, as well as for multiple commercial and industrial applications. 

Neodymium Block Magnets Specification

Dimensions

Per your request or drawing

We can customized as required

Properties (Theoretical)

The most appropriate temperature for Neodymium Magnets

The performance of a neodymium magnet is affected by temperature. As the temperature gets colder, neodymium magnets get stronger, and they even operate better at lower temperatures. Neodymium magnets are said to be able to function well in temperatures as low as -130 ° C.  It is also possible for certain grades of neodymium magnets to be exposed to very high temperatures before they begin to change their properties and, either temporarily or permanently, lose their magnetism. 

Neodymium Magnets decrease in magnetic strength by 0.11% for every degree celsius of temperature increase. If the maximum operating temperature is not exceeded, this small loss can be fully recovered on cooling. In the case of exceeding it, the small loss will not be recovered on cooling. The magnetic field output of Neodymium magnets increases with temperature up to 80° C and after that point, they begin to lose their effectiveness. There are different levels of Neodymium 35 temperature rating (M, H, SH, UH, EH, or AH). Higher temperature versions (NxxM, NxxH, NxxSH, NxxUH, NxxEH, NxxVH/AH) are rated from up to +100⁰ C to a maximum of up to +230 ⁰ C.  The magnetic performance will continue to decline after successive hot-cold cycles. Without careful design of the magnetic circuit, you should not use these magnets in temperatures above 130° C (240° F).

The permanent demagnetisation fields and radiation can also affect neodymium magnets, so the magnet must always be fully understood according to the environment in which it will be used.

Neodymium Magnets require surface treatments

In humid conditions, magnets without a surface coating (such as plating) may rust. Therefore, all  Neodymium Magnets or Rare Earth magnets should have some form of protective coating to minimise and ideally prevent corrosion. Uncoated is not advised. The default / standard protective coating is Ni−Cu−Ni plating. Other coatings/finishes exist (over 40 finishes are currently available). Where maximum corrosion resistance is required for NdFeB, consider using the increased corrosion resistance range of NdFeB alloys.

Advantages & Disadvantages of Neodymium Magnets (NdFeB)

Advantages 

· Maximum performance relative to size. Ideal for restricted space or compact applications. 

· Can be used in extremely cold conditions (e.g. in liquid nitrogen).

· Standard Neodymium NdFeB Magnet is rated to +80 degrees C (176F) maximum. Can be rated to +100 (212F), +120 (248F), +150 (302F), +180 (356F), +200 (392F) and +220/230 degrees C (428/446F) with higher Hci versions.

· High coercivity (Hci) to resist demagnetisation.

· NxxT and L-NxxT alloys have better corrosion resistance than standard NdFeB but still needs coating.

Disadvantages

· Requires a protective coating to prevent the iron in the alloy from corroding (rusting).

· NxxT and L-NxxT alloys are much more expensive and will still show signs of corrosion.

· Higher temperature versions contain more Dy element increasing their cost.

· Nd and Dy prices affect the production cost.

Above 150-180 deg C (302-356F), SmCo may be better

Features include:

• Neodymium magnets are the most powerful commerically produced magnets.

• Neodymium magnets are hard and brittle and may chip or break if dropped.

• Disc Neodymium magnets are magnetized through the thickness or diametrically magnetized.
• Uncoated neodymium magnets may corrode in humid conditions
• Operating temperatures vary among material grades.Usually ranges from 80°C to 220°C. 
• Keep cautious when handling magnetized neodymium magnets, their exceptional magnetic force may cause them to attract to metal (or to each other) so strongly that fingers in their path could prove painful.

Typical Applications for Rare Earth Neodymium Magnets

Neodymium magnets are available in several different sizes and variations, including neodymium bar magnets or neodymium blocks, neodymium disc magnets, neodymium pot magnets, neodymium ring magnets. They are also available with attachments such as hooks or threaded  attachments. They are also available with rubber coatings or adhesive backings. This gives a vast choice to suit a variety of applications including:

· Neodymium Magnets for Motor and Generator drives including, wind and tidal turbines 

· Meters

· Neodymium Magnet Speaker, Audio Equipment - headphones, microphones

· Computer Disc Drives and Printers

· Automotive (clamps, sensors, alternators, interior trims)

· Precision Magnets for Aerospace - sensors, navigation equipment

· Fine particle Magnetic Separation (magnetic rods, magnetic grids, etc) – 10-12kG (22-26lbs) systems

· High-performance magnetic clamps and pot magnets

· Electronics  - switches, relays, sensors

· Lifting Heavy Ferrous materials - see neodymium magnetic lifters   

Packing of Neodymium Block Magnets

Standard Packing:

Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 440 gallon liquid totes Special package is available on request.

ATTs’ Neodymium Block is carefully handled to minimize damage during storage and transportation and to preserve the quality of our products in their original condition.

Chemical Identifiers