NEODYMIUM MAGNETS
High Performance Neodymium Magnets
Usually known as NdFeB (Neodymium-Iron-Boron) magnets, neodymium (Nd), iron (Fe), and boron (B) define a family of permanent magnets. These have extraordinary magnetic qualities and are among the strongest known magnets. The special electrical structure of the neodymium atom generates a high magnetic field, which lets neodymium magnets be much stronger than many other magnets of comparable mass.
NdFeB Magnets In Superior Grades & Finishes
Superior magnetic characteristics allow neodymium magnets to operate appropriately, given size and form. Common shapes include discs, cubes, bars, rings, rods, countersunks, channels, pots, and hook forms. Each one might be chosen depending on its need for a particular use.
Neo Magnet Features & Characteristics
- Are neodymium magnets harmful to health? Neodymium magnets are harmless, but their strong magnetism may interfere with pacemakers. Be careful when using them to avoid injury.
- How to use neodymium magnets safely? Avoid high temperatures, avoid contact with electronic devices, and avoid impact and extrusion during storage.
- How strong is the magnetic force of neodymium magnets? Neodymium magnets are currently the strongest permanent magnetic materials. The magnetic force varies according to the grade (such as N35 and N52), and the N55 grade is the strongest.
- Will neodymium magnets demagnetize? Under normal conditions, neodymium magnets will not demagnetize, but high temperatures or shocks may cause the magnetic force to weaken.
- How do we test the magnetic force of neodymium magnets? Use a magnetometer (Gaussmeter) to test the magnetic field strength or indirectly judge by the ability to adsorb metal objects.
- Can neodymium magnets be used at high temperatures? The working temperature of neodymium magnets is generally between -40 °C and 80°C. If it exceeds this range, it may demagnetize.
- Are neodymium magnets suitable for outdoor use? Neodymium magnets are not resistant to moisture. For outdoor environments, it is recommended to choose magnets that have been treated with anti-corrosion.
- How to avoid neodymium magnets from breaking? Avoid strong impact and extrusion. Place them on a soft cushion surface during storage to avoid forced contact with other magnets.
- Why does the surface of neodymium magnets need to be treated? Surface treatments (such as nickel and zinc plating) can improve corrosion resistance and extend service life.
NdFeB Grade Maximum Operating Temperatures
Understanding the maximum operating and curie temperatures of neodymium magnets is crucial for selecting the right magnet and ensuring its stable performance.
*Highest Operating Temperature: The highest temperature at a magnet can sustain its magnetic performance under particular operating circumstances. Beyond this temperature, magnetic performance diminishes extremely fast, decreasing its efficacy.
*Curie Temperature: The temperature at which a magnet loses its magnetism and cannot be re-magnetized.
Coating (surface treatment)
Because neodymium magnets are prone to oxidation and corrosion, coatings stop rust and shield their vulnerable surfaces. Choosing the correct coatings for neodymium magnets may be difficult, given their great range. We have included the chart below to help you select the appropriate course of action depending on your requirements.
| Coating | Color | Indoors | Humidity | Water | Thickness (µm) |
|---|---|---|---|---|---|
| Nickel (Ni-Cu-Ni) | Bright silver | Good | Okay | Bad | 5-20 |
| Gold plating (Ni-Cu-Ni-Au) | Golden | Good | Okay | Bad | 5-20 |
| Chrome (Ni-Cu-Ni-Cr) | Dark black | Good | Okay | Bad | 5-20 |
| Epoxy resin (Ni-Cu-Ni-Epoxy) | Black | Good | Good | Okay | 15-65 |
| Zinc (Zn) | Blue & white | Good | Okay | Bad | 4-15 |
| Nickel-zinc (Ni-Cu-Ni-Zn) | Bright color | Good | Okay | Bad | 4-15 |
| Non-stick coating (PTFE/PFAS) | Dark grey | Good | Good | Okay | 15-65 |
| Silver (Ni-Cu-Ni-Ag) | Silver | Good | Okay | Bad | 5-20 |
Manufacturing Process
The production process of NdFeB permanent magnetic materials is complex and precise, encompassing multiple manufacturing stages, primarily involving the following six key steps.
strip casting
Hydrogen decrepitation
Mixing
Magnetic Powder Alignment & Molding
Sintering
Tempering
1. Strip casting
2. Hydrogen decrepitation
3. Mixing
4. Magnetic Powder Alignment & Molding
One important process for improving the magnetic performance of sintered NdFeB magnets is magnetic powder orientation. The hydrogen-exploded magnetic powder is loaded in a mold, and an external magnetic field is applied to orient the magnetic domains of the powder particles. This process results in the formation of a stronger oriented magnetic field after sintering, hence giving a higher magnetic energy product and coercivity in the final magnet.
5. Sintering
6. Tempering
Tempering is a process of reheating the magnet at an appropriate temperature to stabilize the grain boundary after sintering, and it optimizes the microstructure of sintered NdFeB magnets and enhances their magnetic properties further.
Magnetization Pattern and Direction
Sintered neodymium magnets are anisotropic and can only be magnetized in the predetermined direction. Generally, the magnets are axially magnetized (magnet in round shape) or magnetized through thickness (magnet in square or rectangular shape).
Axially Magnetized
Diametrically Magnetized
Magnetized thru Circumference
Magnetized thru Circumference
Magnetized North Outer Face
Magnetized North Outer Face
NdPr Raw Material Price for Neodymium Magnets
Fluctuations in the price of NdPr (neodymium-praseodymium alloy) directly influence the manufacturing cost and market pricing of neodymium magnets. Changes in the price of NdPr are a significant predictor of the price trend in the neodymium magnet market, as they are the main raw material for these magnets.
