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        History of development

        Silicon carbide rod is a high temperature electric heating element made of silicon carbide as an important raw material. After the synthesis of silicon carbide at the end of the 19th Century, the silicon carbide rods were made by the German and Han people in 1905 by the synthesis method. In 1908, the Siemens enterprise produced silicon carbide rods with industrial prices. The product name was "Selit". In 1955, Shenyang Forging Research Institute, Beijing Pig Iron Research Institute, Zhangdian Grinding Wheel Factory (predecessor of Fourth Grinding Wheel Factory), Sujiatun Grinding Wheel Factory (predecessor of Grinding Wheel Factory), Electrical Engineering Research Institute of the Ministry of Mechanical and Electrical Engineering, and Luoyang Refractories of Metallurgy Department In 1957, the discussion institute and other units joined the synthetic experimental group to successfully develop silicon carbide rods in the Fourth Grinding Wheel Factory and start industrial mass production. 
          Silicon carbide rod is a high-temperature electric heating element made of high-purity green silicon carbide, carbon, etc. through high-temperature silicidation and recrystallization. Its silicon carbide content is more than 98%, so it has the same physical and chemical properties as silicon carbide. Compared with electric heating elements, it has the following unique advantages: 
          1. Strong acid resistance and strong chemical resistance; 
          2.Surface charge density greater than the metal heating element, rapid heating, high thermal efficiency; 
          3. 3. Good resistance to rapid heat and cooling, and small linear expansion parameters; 
          4. High thermal conductivity; 
          5.High temperatures, long furnace, a normal oxygen atmosphere, the rod surface temperatures can reach 1600 deg.] C, using a series of up to 2000h furnace above; 
          6. Easy to install and replace; 
          7.Sources of materials are wide. 
          Because of its unique and excellent functions, silicon carbide rods are deeply used in various electric kilns with furnace temperatures of 600-1500℃ for smelting, electronics industry, kiln industry, chemical industry, metal heat treatment, sintering of powder smelting, porcelain, science Cited in experiments, etc. The silicon carbide rod is also applied to the instrument as an orange infrared light source and is an ideal high-temperature electric heating element.
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