Silicon micropowder is an amorphous (non-crystalline) polymorph of silica. Generally speaking, each ton of metal silicon produced can produce 0.3-0.5 tons of silicon micropowder by-product. Silicon micropowder is sometimes confused with fumed silica. The average particle size of silicon micropowder is 150 nm, which is 100 times smaller than cement particles, and the specific surface area is 15~30 m 2 /g. The primary particle size of fumed silica is only about 5-7 nm, and the specific surface area is as high as 150~300. Square meters / gram. The main application area of silicon micropowder is as a reinforcing filler for high performance concrete, especially to improve its comprehensive strength, bond strength and wear resistance. The addition of silicon micropowder can also reduce the permeability of chloride ions to concrete and prevent corrosion of steel in concrete. In addition, silicon micropowder is also widely used in ceramics and refractory materials.