1, Rare earths are known as "industrial vitamins". Now it has become an extremely important strategic resource. Rare earth oxides are 15 lanthanide oxides with atomic numbers from 57 to 71 in the periodic table, and the oxides of 17 elements, SC and YY), which are similar to lanthanide chemical properties. Rare earth elements have been widely used in petroleum, chemical, metallurgical, textile, ceramic, glass, permanent magnetic materials and other fields. With the development of science and technology and the breakthrough of application technology, the value of rare earth oxide will be more and greater.
2, Magnetic material, usually referred to as the strong magnetic material
, which is old and widely used functional material. The magnetic material can be divided into soft magnetic material and hard magnetic material according to the difficulty of demagnetization after magnetization. A substance that is easy to remove after magnetization is called a soft magnetic material. Substances that are not easy to demagnetize are called hard magnetic materials. Generally speaking, the remanence of soft magnetic material is smaller, the remanence of hard magnetic material is larger.
3, Rare earth is one of the raw materials of magnetic materials, such as rare earth permanent magnetic materials. In other words, rare earths can be used to produce magnetic materials.
4, Rare earth
permanent magnetic materials are alloys composed of samarium and neodymium mixed rare earth metals and transition metals (such as cobalt, iron, etc.), Pressing mould sintered by powder metallurgy method and magnetized by the magnetic field.
5, Rare earth permanent magnet includes Sm-Co permanent magnets and NdFeB permanent magnets. The magnetic energy product of SmCo magnets ranges from 15 to 30 MGOe. The magnetic energy product of NdFeB magnets is between 27 and 52 MGOe, so it is called "permanent magnet king". and it is the most magnetic permanent magnet material so far. Samarium cobalt permanent magnet, despite its excellent magnetic properties, contains rare earth metal samarium and rare and expensive strategic cobalt, so its development is greatly limited. The development of rare-earth permanent magnet industry in China began in the late 1960s, the dominant product at the time was samarium cobalt permanent magnets, the world' s sales of Sm-Co magnet world was 630 tons, 90.5 tons in China (including SmCo magnetic powder), mainly used in military technology