Application of scandium oxide
The chemical formula of scandium oxide is Sc2O3. Properties: White solid. With cubic structure of rare earth sesquioxide. Density 3.864. Melting point 2403℃ 20℃. Insoluble in water, soluble in hot acid. Is prepared by thermal decomposition of scandium salt. It can be used as evaporation material for semiconductor coating. Make solid laser with variable wavelength, high definition TV electron gun, metal halide lamp, etc.
Scandium oxide (Sc2O3) is one of the most important scandium products. Its physical and chemical properties are similar to those of rare earth oxides (such as La2O3,Y2O3 and Lu2O3, etc.), so the production methods used in production are very similar. Sc2O3 can produce metal Scandium (sc), different salts (ScCl3,ScF3,ScI3,Sc2(C2O4)3, etc.) and various scandium alloys (Al-Sc,Al-Zr-Sc series). These scandium products have practical technical value and good economic effect.Sc2O3 has been widely used in aluminum alloy, electric light source, laser, catalyst, activator, ceramics, aerospace and so on because of its characteristics. At present, the application status of Sc2O3 in the fields of alloy, electric light source, catalyst, activator and ceramics in China and the world is described later.
(1) the application of alloy
At present, the Al-Sc alloy made of Sc and Al has the advantages of low density (SC = 3.0g/cm3,Al = 2.7g/cm3, high strength, high hardness, good plasticity, strong corrosion resistance and thermal stability, etc. Therefore, it has been well applied in the structural parts of missiles, aerospace, aviation, automobiles and ships, and gradually turned to civilian use, such as the handles of sports devices (hockey and baseball)It has the characteristics of high strength, high rigidity and light weight, and is of great practical value.
Scandium mainly plays the role of modification and grain refinement in the alloy, which leads to the formation of new phase Al3Sc type with excellent properties. Al-Sc alloy has formed a series of alloy series, for example, Russia has reached 17 kinds of Al-Sc series, and China also has several alloys (such as Al-Mg-Sc-Zr and Al-Zn-Mg-Sc alloy). The characteristics of this kind of alloy can not be replaced by other materials, so from the development point of view,Its application development and potential are great, and it is expected to become a big application in the future. For example, Russia has industrialized production and developed rapidly for light structural parts, and China is speeding up its research and application, especially in aerospace and aviation.
(2) the application of new electric light source materials
Pure Sc2O3 was converted into ScI3, and then made into a new third generation electric light source material with NaI, which was processed into scandium-sodium halogen lamp for lighting (about 0.1mg~ 10mg of Sc2O3≥99% material was used for each lamp. Under the action of high voltage, the scandium spectral line is blue and the sodium spectral line is yellow, and the two colors cooperate with each other to produce light close to sunlight.The light has the advantages of high luminosity, good light color, energy saving, long life and strong fog breaking power.
(3) Application of laser materials
Gadolinium gallium scandium garnet (GGSG) can be prepared by adding pure Sc2O3≥ 99.9% to GGG, and its composition is Gd3Sc2Ga3O12 type. The emission power of the third generation laser made of it is 3.0 times higher than that of the laser with the same volume, which has reached a high-power and miniaturized laser device, increased the output power of laser oscillation and improved the performance of laser. When preparing a single crystal,Each charge is 3kg~ 5kg, and about 1.0kg of raw materials with Sc2O3≥99.9% are added. At present, this kind of laser is widely used in military technology, and it is also gradually pushed to civilian industry. From the perspective of development, it has great potential in military and civilian use in the future.
(4) the application of electronic materials
Pure Sc2O3 can be used as oxidation cathode activator for cathode electron gun of color TV picture tube with good effect. Spray a layer of Ba, Sr and Ca oxide with a thickness of one millimeter on the cathode of the color tube, and then disperse a layer of Sc2O3 with a thickness of 0.1 millimeter on it. In the cathode of the oxide layer, Mg and Sr react with Ba, which promotes the reduction of Ba, and the released electrons are more active, giving off large current electrons, which makes the phosphor emit light.Compared with the cathode without Sc2O3 coating, it can increase the current density by 4 times, make the TV picture clearer and prolong the cathode life by 3 times. The amount of Sc2O3 used for each 21-inch developing cathode is 0.1mg At present, this cathode has been used in some countries in the world, such as Japan, which can improve the market competitiveness and promote the sales of TV sets.
Post time: Aug-10-2021