Can Neodymium Magnets Recover After Demagnetization at High Temperatures?

The applications of high-strength neodymium-iron-boron magnets span a wide range of industries. Depending on the specific field and product, the requirements for the magnets vary—such as resistance to high temperatures, salt spray resistance and dimensional tolerances. Some purchasers, perhaps due to a lack of understanding of magnets, may fail to inform the manufacturer of the need for high-temperature resistance, or they may simply find specifications online that seem suitable and, if the price is acceptable, proceed to make a purchase. However, this can easily lead to demagnetisation during use. Alternatively, magnets that do not require magnetisation may be magnetised by mistake because the requirements were not clearly communicated to the manufacturer.

So, can high-performance neodymium magnets be remagnetised after demagnetisation at high temperatures?

The answer is that they can be remagnetised, but they will not return to their original level. In other words, their intrinsic magnetic properties have deteriorated and cannot be fully restored. It is therefore essential to understand the operating temperatures of various magnets.

Neodymium block magnets for use in electric motors

Drawbacks of remagnetising neodymium-iron-boron magnets after high-temperature demagnetisation:

Loss of magnetism: Following high-temperature treatment, the microstructure inside the magnet may have changed, leading to partial or complete loss of magnetism. Even if remagnetised, its magnetism may not fully return to its previous level.

Structural changes: High temperatures may alter the crystal lattice structure within the magnet, making it more brittle or susceptible to fracture from external impacts.

Cost and efficiency: The remagnetisation process may require additional time and resources, whilst it may not fully restore the original magnetic properties.

Worth knowing;

Maximum working temperature and Curie temperature of neodymium magnets

Will neodymium magnets demagnetize when exposed to instantaneous high temperatures?