Microsilica which plays a vital role in
the physical and chemical properties of fresh and hardened
concrete has been used worldwide in the
construction of skyscrapers, bridge construction, marine
structures, roads, railways and seaports because it
ensures the durability of these structures.Technology
Microsilica is a mineral composed of ultra-fine amorphous spheres of silicon dioxide (SiO2), produced during the manufacture of silicon or ferrosilicon. This tightly controlled electro-metallurgical process involves the reduction of high-purity quartz in electric arc furnaces at temperatures of over 2,000 deg C.
Microsilica is formed when SiO gas, given off as the quartz reduces, mixes with oxygen in the upper parts of the furnace. Here the SiO is oxidised to SiO2, condensing into the pure spherical particles of microsilica forming the major part of the smoke or fume from the furnace. Hence the alternative names for the material – condensed silica fume, silica fume, densified silica fume, silica powder, amorphous silica, silicon dioxide powder or condensed SiO2 fume.