Yingjie jisb2812sa's blog : The content of silicon in the Earth's crust is only second
Understanding the components of siliconmetal is conducive to grasp various properties of silicon metal, then betteruse of silicon metal.Silicon L-bolts Factory metal is the product composed of quartz andcoke smelting in electric furnace, the main component of silicon content isaround L Shaped Bolts 98%, the remaining impurities are iron, aluminium, calcium and so on.Silicon metal (also known as Silicon in China) is a product name appears in60 medium-term of this century. Its emergence is related to the rise ofsemiconductor industry. At present, international practice is divided siliconinto metallic silicon and silicon products.
Semiconductor silicon used for theproduction of semiconductor devices high-purity silicon metal. Are based onpolycrystalline and single crystal form for sale, the price the former is cheap,the latter is expensive.The classification of silicon metal is usually accordingto the three main impurities of iron, aluminium and calcium content in siliconmetal component. Industrially, silicon metal is usually determined by carbonreducing silica in electric furnace. The purity of silicon produced by thismethod is 97~98%, called silicon metal. Then recrystallize after melting,remove impurities with acid to get silicon metal, which the purity is99.7~99.8%.Silicon metal composition was mainly the silicon, sothat have similar property with silicon. Silicon has amorphous silicon powder andcrystalline silicon two allotropes. Amorphous silicon powder is dark gray powder,is actually a micro-crystal.
Crystalsilicon has diamond crystal structure and semiconductor properties. Amorphoussilicon powders chemical property is lively, intense burning in oxygen. Can reactwith halogens, nitrogen, carbon and other non-metallic at high temperature, alsocan react with magnesium, calcium, iron and other metals to generate silicide.Amorphous silicon powder almost insoluble all inorganic acids and organic acids excepthydrofluoric acid, but can be dissolved in the mixture of nitric acid and hydrofluoricacid. Concentrated sodium hydroxide solution can dissolve the amorphous siliconpowder, releasing hydrogen gas. Crystal silicon is less lively, even if in theheat were not combined with oxygen, it also can not soluble in any inorganicacids and organic acids, but dissolve in the mixture of nitric acid andhydrofluoric acid and concentrated sodium hydroxide solution.Semiconductor silicon used for producingsemiconductor devices high-purity silicon metal. Because of their differentuses, they can be divided into a variety of specifications. According to metal powder supplier research, in 1985, the world consumes about 500,000 tons of siliconmetal, of which used for aluminum alloy is accounted 60%, used for silicone isless than 30%, for semiconductors accounted for about 3% and the rest used foriron and steel making and precision ceramics.
The content of silicon in the Earth's crust is only second to oxygen, up to 25.8%. Silicon metal in nature is mainly in the form ofcombining with oxygen into silicon dioxide, or metal silicates, the purestsilica mineral is quartz and silica. The property of silicon metal is closed tosilicon, germanium, tin, lead. Silicon is extensively used for ferrosiliconsmelting, as the alloying element in iron and steel industry, as a reducingagent in many kinds of metals smelting. Silicon metal is also a good set ofaluminum alloy, the vast majority casting aluminum alloys were containing siliconmetal.