Silica fume and silica powder are two different products. Due to the silica fume and silica powder in different industries are widely used, coupled with regional and industry restrictions by a part of the enterprise and staff, mistakenly considered to be the same product.
Appearance
Silica fume
Appearance of silica fume: dark blue, dark blue black, gray, gray and slightly white.
The specific gravity of silica fume is relatively light: original gray>half-encrypted>full encrypted into a sphere.
Silica ash has a delicate feel without roughness, and more slippery. Silicon dioxide content is generally between 80~99%.
Silica powder
Silica powder is crystallized silicon dioxide, which is made from natural quartz (SiO2) or fused quartz (natural quartz amorphous SiO2 after high-temperature fusion and cooling) through crushing, ball milling (or vibration, air flow milling), flotation, purification by acid washing, high-purity water treatment and other processes. silica powder is a kind of non-toxic, odorless, non-polluting inorganic non-metallic material.
Silica powder appearance: white, slightly white. The specific gravity is relatively heavy, like stone powder.
Parameters
Silica fume
Silica fume appearance of gray or off-white powder, refractoriness > 1600 ℃. Weight: 200 ~ 250 kg / cubic meter. Silica fume fineness less than 1um accounted for more than 80%, the average particle size of 0.1 ~ 0.3um, specific surface area: 20 ~ 28m2 / g. Its fineness and specific surface area of about 80 ~ 100 times the cement, fly ash 50 ~ 70 times!
Silica powder
The common specifications of silicon micropowder are 400 mesh, 800 mesh, 1000 mesh, 1500 mesh and 2000 mesh fine powder. Silica powder has a rough feel and no slippery feeling. The content of silicon dioxide is 98~99.99%.
Applications
Silica fume
Silica fume is mainly used in: commercial concrete, high-strength concrete, self-leveling concrete, unshaped refractory materials, dry mix (ready-mixed) mortar, high-strength non-shrinkage grout, wear-resistant industrial flooring, repair mortar, polymer mortar, thermal insulation mortar, seepage-resistant concrete, concrete compacting agent, concrete anticorrosive agent, cementitious polymer waterproofing agent; rubber, plastics, unsaturated polyester, paints, coatings, as well as other polymer materials, reinforcing, ceramics, and so on. Modification of ceramic products and so on.
Silica powder
It is widely used in chemical industry, electronics, integrated circuits (IC), electrical appliances, plastics, paints, advanced paints, rubber, national defense and other fields because of its excellent properties such as good temperature resistance, acid and alkali corrosion resistance, poor thermal conductivity, high insulation, low expansion, stable chemical properties, high hardness and so on. With the rapid development of the field of high technology, silica powder will also step into a new period of historical development.