The neodymium iron boron magnets are currently recognized high-performance and cost-effective magnets in the magnetic material industry. Many high-tech fields have designated them to make various parts, such as national defense military, electronic technology, medical equipment, Electrical machinery and other fields are involved. The more it is used, the easier it is to find the problem. Among them, the demagnetization phenomenon of neodymium iron boron strong magnets in high temperature environments has attracted much attention.
Why does NdFeB demagnetize in high temperature environment?
The reason why NdFeB demagnetizes in a high temperature environment is determined by its physical structure. Generally, a magnet can generate a magnetic field because the electrons carried by the substance itself rotate in a certain direction around the atom, thereby generating a certain magnetic field force, which in turn has an impact on the surrounding affairs. However, electrons revolve around atoms in a predetermined direction are also subject to certain temperature conditions. Different magnetic materials can withstand different temperatures. In the case of excessively high temperatures, the electrons will deviate from the original orbit and cause chaos. This At that time, the magnetic field of the magnetic substance itself will be disrupted, resulting in demagnetization.
The temperature resistance of neodymium iron boron magnets is about two hundred degrees, that is, demagnetization will occur if the temperature exceeds two hundred degrees. If the temperature is higher, the demagnetization will be more serious. Is magnet demagnetization permanent or temporary at high temperature?
The Curie temperature of neodymium iron boron is 320C-380°C, but in fact the molecular structure of neodymium iron boron has changed when it is heated, and the magnetic force will fade if it does not reach the theoretical Curie temperature. The temperature resistance of the neodymium iron boron in the experiment is 100 degrees. When it is heated to about 100 degrees, the magnetic force begins to decrease, but the speed does not turn on. After 150 degrees, the magnetic force drops significantly after 150 degrees, and the magnetic force basically fades after maintaining 150 degrees for 20 minutes. After demagnetizing the demagnetizing magnetic NdFeB, it can only reach about 50% of the original value. Moreover, the surface appears blackened and oxidized.
The most effective solutions for high temperature demagnetization of neodymium iron boron magnets
1.Don't put NdFeB magnet products in high temperature, especially pay attention to its critical temperature, that is, two Baidu. Adjust its working environment temperature in time to minimize the occurrence of demagnetization.
2.2. start with technology to improve the performance of products using neodymium iron boron magnets, so that they can have a higher temperature structure and are not easily affected by the environment.
3. You can also choose high-coercivity materials with the same magnetic energy product. If it still doesn’t work, you can only sacrifice a little magnetic energy product to find a higher coercivity material with a lower magnetic energy product. For the demagnetization, the only choice is samarium cobalt.
