Here we will talk about the timing of the application of various rare earth elements in order to make a better distinction between light rare earth and heavy rare earth:
Promethium (Pm) : promethium is a man-made radioactive element produced in nuclear reactors. For vacuum detection and satellite to provide auxiliary energy. Pm147 gives off rays of low energy to make promethium batteries. Power for missile guidance instruments and clocks. The batteries are small and can last for years. Promethium is also used in portable X-ray machines, making phosphors, measuring thickness and in navigation lights.
Samarium (Sm) : samarium cobalt magnets were the first rare earth magnets used in industry. This kind of permanent magnet has SmCo5 series and Sm2Co17 series. SmCo5 series was invented in the early 1970s, and Sm2Co17 series was invented later. Now it is mainly the demand of the latter. The purity of samarium oxide used for samarium cobalt magnets need not be too high. Considering the cost, about 95% of the products are mainly used. Samarium oxide is also used in ceramic capacitors and catalysts. Samarium also has nuclear properties and can be used as structural material, shielding material and control material for atomic reactors, allowing the safe use of the enormous energy generated by nuclear fission.
Europium oxide (Eu) : most of europium oxide is used in phosphors. Eu3+ is used as an activator for red phosphors and Eu2+ for blue phosphors. Y2O2S:Eu3+ is the best phosphor with luminous efficiency, coating stability and recovery cost. Coupled with improvements in luminescence efficiency and contrast, it is being widely used. Europium oxide has also been used as stimulated emission phosphor in new X-ray medical diagnostic systems. Europium oxide can also be used in the manufacture of coloured lenses and optical filters, magnetic bubble storage devices and in the control, shielding and structural materials of atomic reactors.
Gadolinium (Gd) : 1, its water-soluble paramagnetic complex can improve the body’s nuclear magnetic resonance (NMR) imaging signal in medical treatment. Its sulfur oxides can be used as matrix grids for special brightness oscilloscopes and X-ray screens. 3. Gadolinium in gadolinium gallium garnet is an ideal single substrate for magnetic bubble memory. 4. In the absence of Camot cycle limit, it can be used as solid magnetic refrigerating medium. 5. Used as an inhibitor to control the chain reaction level of nuclear power plants to ensure the safety of nuclear reactions. 6. Used as additive for samarium cobalt magnets to ensure performance does not change with temperature. In addition, the use of gadolinium oxide and lanthanum together can help to change the glass area and improve the thermal stability of the glass. Gadolinium oxide is also used in the manufacture of capacitors and X-ray sensitized screens. At present, efforts are being made to develop the application of gadolinium and its alloy in magnetic refrigeration in the world, and a breakthrough has been made. Magnetic refrigerators using superconducting magnets, metal gadolinium or its alloy as the refrigerating medium at room temperature have come out.
Biterbium (Tb) : 1. Phosphor is an activator of green powder in tribasic phosphor, such as terbium-activated phosphate matrix, terbium-activated silicate matrix and terbium-activated cerium magnesium aluminate matrix. 2. Magneto-optic storage material: in recent years, the magneto-optic material of terbium series has reached the scale of mass production. Magneto-optic optical disc developed with tb-fe amorphous film is used as the computer storage element, and the storage capacity is increased by 10-15 times. 3. Magneto-optic glass, Faraday rotatory glass containing terbium, is the key material for manufacturing rotators, isolators and annular devices widely used in laser technology. In particular, the development of TerFenol, a dysprosium ferromagnetic alloy, has opened up new USES for terbium. When TerFenol is placed in a magnetic field, the size of TerFenol changes more than that of ordinary magnetic materials. Such changes can enable some precision mechanical movements. Ferrosium terbium, used primarily in sonar, has been used in a wide range of applications, from fuel injection systems, liquid valve control, micropositioning to mechanical actuators, mechanisms and wing regulators for aircraft space telescopes.
Dysprosium (Dy) : 1, used as an additive of ndfeb permanent magnet, adding dysprosium of about 2~3% in this magnet can improve its coercivity. In the past, dysprosium was not in great demand, but with the increase of ndfeb magnet demand, it becomes a necessary addition element, the grade must be around 95 ~ 99.9%, the demand is also increasing rapidly. Dysprosium is used as an activator of phosphor powder. Dysprosium trivalency is a promising activated ion of single-luminescent center tricolor luminescent material. It is mainly composed of two emission bands, one is yellow light emission and the other is blue light emission. 3. Dysprosium is a necessary metal raw material for the preparation of Terfenol alloy, a large magnetostrictive alloy, which enables the realization of some precision activities of mechanical movement. Dysprosium can be used as a magneto-optical storage material, with high recording speed and reading sensitivity. 5. For the preparation of dysprosium lamps, dysprosium iodide is used as the working substance in dysprosium lamps. Such lamps have the advantages of high brightness, good color, high color temperature, small size and stable arc, etc., and have been used for lighting sources such as films and printing. 6. Dysprosium is used for the determination of neutron energy spectrum or as a neutron absorber in the atomic energy industry due to its large neutron capture cross-sectional area. Dy3Al5O12 can also be used as magnetic working material for magnetic refrigeration. With the development of science and technology, dysprosium applications will continue to expand and extend.
Holmium (Ho) : 1, used as an additive to metal halogen lamps, which are gaseous discharge lamps developed from high-pressure mercury lamps and characterized by the filling of various rare earth halides in the bulbs. At present, rare earth iodides are mainly used, which emit different spectral colors during gas discharge. The working substance used in holmium lamp is iodinated holmium, which can obtain high metal atomic concentration in the arc region, thus greatly improving the radiation efficiency. 2, holmium can be used as an additive to yttrium iron or yttrium aluminum garnet. 3. Ho: yttrium aluminum garnet (Ho:YAG) doped with holmium can emit 2 m laser, and human tissues have a high absorption rate of 2 m laser, almost 3 orders of magnitude higher than Hd:YAG. Therefore, Ho:YAG laser can not only improve the efficiency and accuracy of surgery, but also reduce the area of thermal damage. Holmium crystals produce a free beam that removes fat without generating excessive heat, thereby reducing the thermal damage to healthy tissue. It has been reported that treating glaucoma with holmium laser in the United States can reduce the pain of surgery. The level of 2 m laser crystal in our country has reached the international level. 4. A small amount of holmium can also be added to the magnetostrictive alloy terfenol-d to reduce the external field required for saturation magnetization of the alloy. 5. In addition, holmium doped fiber can be used to make fiber laser, fiber amplifier, fiber sensor and other optical communication devices, which will play a more important role in today’s rapid optical communication.
Erbium (Er) : 1, Er3 + light emission at 1550 nm with special significance, because the wavelength is just the minimum loss in optical fiber communication optical fiber, erbium ions (Er3 +) by the wavelength of 980 nm, 1480 nm light excitation, 4 i15/2 from the ground state transition to upper state 4 i13/2, when in the upper state Er3 + to transition back to the ground state when emit 1550 nm wavelength of light, quartz optical fiber can transmit different wavelengths of light, but different light failure rate is different, in the light of 1550 nm band quartz optical fiber transmission attenuation time minimum (0.15 db/km), Is almost the lower limit attenuation rate. Therefore, optical loss is minimized when optical fiber communication signals at 1550nm. So, if the appropriate concentration of erbium doped suitable matrix, can according to the principle of laser effect, loss in the amplifier can compensate the communication system, so the need to enlarge the wavelength of 1550 nm light signals in the telecommunications network, erbium-doped fiber amplifier is indispensable optical device, the erbium-doped silica fiber amplifier has been commercialized. It has been reported that in order to avoid unwanted absorption, the amount of erbium doped in the fiber is in the tens to hundreds of PPM. The rapid development of optical fiber communication will open up new application fields of erbium. 2, the additional erbium laser crystal and its output of 1730 nm and 1550 nm laser is safe for people eyes, atmospheric transmission performance is good, the smoke of the battlefield penetration ability is stronger, the secrecy good, not easy to be enemy detection, illuminate large quantities of military targets, has made it safe for military use portable laser range finder. 3, Er3+ can be made into rare earth glass laser material when added to glass, which is the solid laser material with the highest output pulse energy and power at present. 4. Er3+ can also be used as the activated ion of rare earth conversion laser material. 5. In addition, erbium can also be used for decolorization and coloring of lens glass and crystal glass.
Thulium (Tm) : 1, thulium ray source used as medical portable X-ray machine, thulium can after irradiation in the nuclear reactor to produce a X-ray of isotope that can be used to manufacture portable blood irradiation on the instrument, the radiometer can make thulium – 169 is the role of high neutron beam into thulium – 170, emit X-ray irradiation blood and decreased white blood cells, and it is these white blood cells cause of organ transplant rejection, thereby reducing the early rejection of organ. (2) thulium is also widely used in clinical diagnosis and treatment of tumors because of its high affinity to tumor tissues, especially for heavy and light rare earths. 3. Thulium is used as the activator LaOBr:Br (blue) in the X-ray sensitized screen, which can enhance the optical sensitivity and thus reduce the exposure and harm of X-ray to people. Compared with the previous calcium tungstate sensitized screen, the thulium can reduce the X-ray dose by 50%, which has important practical significance in medical applications. Thulium is also widely used as an additive in metal halogen lamps for new lighting sources. 5, Tm3+ can be made into rare earth glass laser material by adding it to the glass, which is the solid laser material with the largest output pulse and the highest output power at present. Tm3+ can also be used as the rare earth on the conversion of laser materials to activate ions.
Ytterbium (Yb) : 1, as a thermal shielding coating material. Ytterbium can obviously improve the corrosion resistance of electrodeposited zinc coating, and ytterbium-containing coating is smaller than ytterbium-containing coating, uniform and compact. 2. Magnetostrictive material. This material has the property of supermagnetostrictive, that is, it expands in a magnetic field. The alloy is mainly composed of ytterbium/ferrite alloy and dysprosium/ferrite alloy, and a certain proportion of manganese is added to produce supermagnetostrictive. 3. Ytterbium element used for pressure measurement, the test has proved that ytterbium element has high sensitivity in the calibration pressure range, and at the same time, it opens up a new way for the application of ytterbium in pressure measurement. The molars cavity is filled with resin-based fillers to replace the amalgam commonly used in the past. 5. Japanese scholars have successfully completed the preparation of ytterbium-doped gadolinium gallium garnet embedded line-guided laser, which is of great significance to the further development of laser technology. In addition, ytterbium is also used in phosphor activators, radio ceramics, computer memory components (magnetic bubble) additives, and glass fiber fluxes and optical glass additives.
Lu: 1, making certain special alloys. Lutetium, for example, can be used for neutron activation analysis. 2. Stable lutetium nuclides play a catalytic role in petroleum cracking, alkylation, hydrogenation and polymerization. 3, yttrium iron or yttrium aluminum garnet add elements to improve certain properties. 4. Raw materials for magnetic bubble storage. 5. A composite functional crystal doped with lutetium aluminum tetraborate yttrium neodymium belongs to the technical field of salt solution cooled growth crystals. Experiments show that lutetium NYAB crystal doped with lutetium is superior to NYAB crystal in optical uniformity and laser performance. 6. Lutetium has been found to have potential applications in electrochromic displays and low dimensional molecular semiconductors by foreign authorities. In addition, lutetium is also used in energy battery technology and as an activator for phosphors.
Yttrium (Y) : 1, additives for steel and nonferrous alloys. FeCr alloys typically contain 0.5-4% yttrium, which enhances the oxidation and ductility of these stainless steels. After adding some yttrium-rich rare earth mixture into MB26 alloy, the comprehensive performance of the alloy is obviously improved, and it can replace part of medium and strong aluminum alloy in aircraft stressed components. A small amount of yttrium-rich rare earth was added to al-zr alloy to improve its conductivity. The alloy has been used in most electric wire factories in China. Yttrium was added to copper alloy to improve electrical conductivity and mechanical strength. 2, yttrium 6% and aluminum 2% silicon nitride ceramic materials, can be used to develop engine parts. 3. The 400w neodymium yttrium aluminum garnet laser beam is used for drilling, cutting and welding of large components. 4. Electron microscope fluorescent screen composed of y-al garnet single chip, high fluorescence brightness, low absorption of scattered light, good resistance to high temperature and mechanical wear. 5, high yttrium structure alloy containing up to 90% yttrium, can be used in aviation and other occasions requiring low density and high melting point. 6. Yttrium-doped SrZrO3 high-temperature proton conduction material, which has attracted much attention at present, is of great significance to the production of fuel cells, electrolytic cells and gas sensitive elements requiring high hydrogen solubility. In addition, yttrium is also used for high temperature resistant spraying materials, nuclear reactor fuel thinner, permanent magnet material additives and as a getter in the electronics industry.
Scandium (Sc) : 1. In the metallurgical industry, scandium is often used in the manufacture of alloys (alloy additives) to improve the strength, hardness, heat resistance and performance of the alloys. For example, adding a small amount of scandium to molten iron can significantly improve the performance of cast iron, and adding a small amount of scandium to aluminum can improve its strength and heat resistance. 2. In the electronic industry, scandium can be used as a variety of semiconductor devices. For example, the application of scandium sulfite in semiconductor has attracted attention at home and abroad. 3. In the chemical industry, scandium compounds are used as dehydrogenation and dewatering agents for alcohol, as well as efficient catalysts for the production of ethylene and chlorine from waste hydrochloric acid. 4. In the glass industry, special glass containing scandium can be made. 5. In the industry of electric light source, scandium sodium lamps containing scandium and sodium have the advantages of high efficiency and positive light color. 6. In nature, all scandium exists in the form of 45Sc. In addition, there are 9 radioactive isotopes of scandium, namely 40 ~ 44Sc and 46 ~ 49Sc. Among them, 46Sc has been used in chemical industry, metallurgy and oceanography as a tracer. 7. In the field of medicine, there are studies abroad using 46Sc to treat cancer.