Will the magnetic properties of this block magnet change in high or low temperature environments?

As the temperature gradually increases, the microstructure inside the block magnet changes significantly. The lattice vibration intensifies, and the distance and arrangement between atoms are affected by thermal disturbances, causing the interaction between magnetic domains to weaken. This weakening is directly reflected in the decrease in saturation magnetization, that is, the maximum magnetization that the magnet can achieve under the action of an external magnetic field decreases. This change is particularly important for applications requiring high magnetic energy products, such as high-performance motors and generators. Coercive force is an important parameter that characterizes the ability of a magnet to resist external magnetic field interference and maintain its own magnetized state. In a high-temperature environment, the change in coercivity is not a single trend, but is affected by multiple factors. On the one hand, the thermal activation effect may cause the magnetic domain walls to move more easily, thus reducing the coercive force to a certain extent; on the other hand, if the material contains additives that can stabilize the magnetic domains or undergoes a special heat treatment process, the coercive force may It will remain stable or even rise slightly within a certain temperature range.
The temperature coefficient of NdFeB magnets is usually negative, and as the temperature increases, the magnetic susceptibility will decrease accordingly. This characteristic significantly reduces the magnetic performance of the magnet in high-temperature environments, limiting its application in extreme temperature conditions. The Curie temperature is an intrinsic property of magnetic materials that marks the critical point at which the material transitions from ferromagnetism to paramagnetism. For NdFeB magnets, although its Curie temperature is much higher than normal temperature, it is still necessary to avoid approaching or exceeding this temperature in practical applications, because even if it is far below the Curie temperature, the magnetic properties will increase with temperature. rise and gradually decline.
Compared with high-temperature environments, low-temperature environments have less impact on the magnetic properties of NdFeB magnets. Within an appropriate low temperature range, the magnetic domain structure of the magnet is relatively stable, and key parameters such as magnetization intensity and coercive force do not change much. This allows NdFeB magnets to maintain good magnetic properties under low temperature conditions and is suitable for applications in some special fields, such as low-temperature superconducting experiments. However, under extreme low temperature conditions, the magnetic properties of NdFeB magnets may also be affected to a certain extent. Although it does not decrease as significantly as high temperatures, the arrangement and stability of magnetic domains may be affected by microscopic mechanisms such as quantum effects, resulting in subtle changes in magnetic properties. In addition, thermal stress caused by extreme temperature changes can also cause damage to magnets.
At extremely low temperatures, while magnets can still function, the magnetic direction may shift and magnetic performance is reduced by about 15 percent. This shows that even at low temperatures, the magnetic properties of magnets are affected to some extent. Of particular note is that if the magnet moves rapidly from a low-temperature environment to a high-temperature working environment, this differential impact of heat may cause damage to the magnet.
Both high temperature and low temperature environments will affect the magnetic properties of NdFeB block magnets. At high temperatures, the magnetic properties will decrease significantly; while at low temperatures, although the effect is relatively small, there will still be some changes at extreme low temperatures. Therefore, when selecting and using NdFeB magnets, it is necessary to evaluate the changes in their magnetic properties based on the specific application environment and requirements.