China's rare earth industry and magnet industry are divided into low-end and high-end industries. Most domestic enterprises are clustered in low-end industries with low technology content. They are in vicious competition with each other and hover between profits and losses.
As for high-end products, the technical threshold will be relatively high. Although China has made great efforts in the research and development of permanent magnets in recent years, and has made many research and development achievements, the most basic patents and standards are controlled by Japanese, American and European enterprises. A few years ago, Chinese enterprises either bought the patent authorization of others or filed a lawsuit while producing. Fortunately, many core patents have passed the protection period in the past two years, which makes Chinese enterprises feel better and can set foot in many fields that cannot be set foot in before.
You may have said, isn't it just a magnet? Everyone knows the composition, and the process is almost understood. The production is finished. How can there be so many patents? It's not that simple! Although NdFeB magnets are strong in magnetism, if they are not well protected, demagnetization is also fast, and the production process of magnets used in different fields is also different.
First of all, rare earth elements are active metals, which are particularly easy to be oxidized. Once oxidized, the magnetism will disappear. Therefore, no matter the production process or the finished product, it is necessary to do a good job of oxidation prevention. If you break the NdFeB magnet, you can generally find that the shiny shell on the surface is just a protective film.
Secondly, the NdFeB magnet itself is particularly afraid of heat, and it is easy to demagnetize when heated, which greatly limits its scope of use. In order to keep its magnetism for a long time and not be easily affected by the outside world, it is necessary to add a protection mechanism to the NdFeB magnet. One of the existing methods is to add a certain amount of dysprosium or terbium. Terbium is the ninth and dysprosium is the tenth of the rare earth elements. Both of them are heavy rare earths, and their reserves on the earth are far less than light rare earths. (Note: Light rare earths include lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, and heavy rare earths include gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, and yttrium. Rare earth minerals in northern China are mainly light rare earth minerals, while those in southern China are heavy rare earth minerals.) It is expensive because it is less. Adding them will increase the production cost of magnets. At present, all countries are studying technologies with little or no dysprosium and terbium, in which Japan and the United States are leading.
Thirdly, there are mainly three different production processes for NdFeB magnets, and China does not have all the advantages. The first is sintered NdFeB technology, which is the largest NdFeB magnet in output. Chinese companies have obvious advantages in output. But the vicious competition is also obvious. The second is bonded NdFeB technology. Magnets produced by this technology are mainly used in hard disk drives and optical drive motors. This technology is more difficult than the previous one, and there are fewer companies to master. Before, the core patents were held by American companies and Japanese companies. Later, the core patents expired, and the output of some Chinese enterprises became higher and higher. China also accounts for more than 70% of the magnets produced by this technology, with nearly 80% of the output. However, joint ventures account for a large proportion. The third is hot pressing/hot deformation NdFeB technology. Megkun Magnetic is the only supplier of its raw materials, fast quenching magnetic powder, and Datong Electronics is the largest manufacturer of MQ - Ⅲ magnets. Chinese companies are getting started.
