Silicon metal, also known as crystalline silicon or industrial silicon, is mainly used as an additive for non-iron based alloys. Silicon metal is a product smelted by quartz and coke in the electric heating furnace. The content of main component silicon element is about 98% (in recent years, 99.99% Si content is also included in silicon metal), and the remaining impurities are iron, aluminum, calcium and so on. The content of silicon is usually above 98.5% and below 99.99%, and the other impurities are iron, aluminum, calcium and so on.


"Metal silicon" (also known as industrial silicon in China) is a commodity name in the mid-1960s. Its emergence is related to the rise of the semiconductor industry. The international common practice is to divide commercial silicon into silicon metal and silicon semiconductor. Silicon metal is a product smelted by quartz and coke in an electric heating furnace. The content of main component silicon element is about 98% (99.99% Si is also included in silicon metal), and the remaining impurities are iron, aluminum, calcium and so on. Semiconductor silicon A high-purity metallic silicon used in semiconductor devices. It is sold in the form of polycrystal and single crystal. The former is cheap and the latter is expensive. Because of its different uses and divided into a variety of specifications. According to statistics, the world's total consumption of silicon metal for aluminum alloy silicon metal accounted for about 60%, less than 30% for organic silicon, for semiconductor accounted for about 3%, the rest for iron and steel smelting and precision ceramics.




Worldwide, the consumption of metallurgical silicon is more than that of chemical silicon, but with the continuous development of science and technology, chemical silicon is used for silicone and semiconductor production and other fields continue to broaden, widely used in the production of silicone monomer and polymer silicone oil, silicone rubber, silicone resin building corrosion, waterproof agent, etc. They have high temperature resistance, electrical insulation, radiation resistance, waterproof and other unique properties. Used in electrical, aviation, machinery, chemical, medicine, national defense, construction and other departments.


Silicon metal is usually classified according to the content of iron, aluminum and calcium, the three main impurities contained in the silicon metal composition. According to the content of iron, aluminum and calcium in silicon metal, silicon metal can be divided into 553, 441, 411, 421, 3303, 3305, 2202, 2502, 1501, 1101 and other different grades.


In industry, silicon metal is usually made by reducing silicon dioxide from carbon in an electric furnace. Chemical reaction equation: SiO2 + 2C → Si + 2CO so that the purity of silicon is 97~98%, called silicon metal. After melting, recrystallization, impurities removed with acid, the purity of 99.7~99.8% silicon metal was obtained.