Silicon is one of the half metal, old name "si". Melting point is 1420 ℃, the density of 2.34 grams per cubic centimeter. Qualitative hard and brittle. At room temperature does not dissolve in acid, soluble in alkali. The nature of the metal silicon and germanium, lead, tin, is in the nature of semiconductor. Silicon in the earth's crust is of rich resources, second only to oxygen, accounting for more than a quarter of the total weight of the earth's crust, in the form of silica or silicate. The most pure silicon minerals are quartz or silica.
There are two allotropes: silicon as a dark brown amorphous powder, nature and lively, can burn in the air. Another into the nature of stable crystal (amorphous silicon). Normally used on glass and other building materials, silica and quartz used to produce high quality quartz and single crystal alloy, metal
Silicon metal (also known as industrial silicon) is emerged in the 20th century 60 s a name of commodity. Metal silicon (Si) is an industrial purification of elemental silicon, mainly for the production of organic silicon, preparing high-purity semiconductor materials and preparation are special-purpose alloy, etc. China is the world's major silicon metal origin, in 2007 China silicon metal production is 95-1 million tons, domestic consumption of silicon metal 250000 tons above, and in recent years, domestic demand for silicon metal is also increasing, the proportion of domestic consumption in production has been improved. China's silicon metal production capacity is large, production mainly concentrated in guizhou, yunnan, fujian, guangxi, sichuan, hunan. Of metallurgical grade silicon metal 553, 441, has a wide distribution area, mainly distributed in guizhou, hunan, sichuan, yunnan, guangxi, Inner Mongolia, xinjiang and other places, including provinces, guizhou is one of the main metal silicon production accounts for 15% to 35% of the national output.
In the next five to 10 years, silicon metal market demand will continue to increase steadily. As the car where more and more popular, aluminum alloy industry, will continue to increase in the amount of silicon metal. In addition, the chemical industry will also become the main power demand of silicon metal. In the next five years, the world average annual growth rate will reach 5% silicon metal demand.
As the global economic integration and international division of labor cooperation in economic development between, China has abundant silica resources, small hydropower resources and cheap labor, China silicon metal industry development prospect is good. Silicon metal production way out is to develop high value-added products. Silicon metal powder, high purity silicon metal, and other products sales in the market price is higher, and the state encourages the production of high value-added products, will also give tax rebates, silicon metal industry in China to develop in the deep processing is a kind of trend.