Industrial silicon fume microsilica 92# 93# 94#

Product Description: Microsilica, also known as silica fume, is referred to as Microsilica or Silica fume in English. It is produced during the smelting of ferrosilicon and industrial silicon (metallic silicon) in submerged arc furnaces, where a large amount of highly volatile SiO₂ and Si gases are generated. These gases are emitted and rapidly oxidize and condense upon contact with air, forming a precipitate. It is a by-product of large-scale industrial smelting processes. The entire production process requires the use of dust removal and environmental protection equipment for recovery. Due to its lightweight nature, densification equipment is also needed for encryption.
?
Physical and Chemical Properties of Microsilica:
1. Silica fume: Appearance is gray or gray-white powder, with a refractory degree >1600°C. Bulk density: 200–250 kg/m³. The chemical composition of silica fume is shown in the table below (the chemical composition varies for different types of silica fume; the following is just an example):
Item SiO₂ Al₂O₃ Fe₂O₃ MgO CaO NaO pH Average
75–98% 1.0±0.2% 0.9±0.3% 0.7±0.1% 0.3±0.1% 1.3±0.2% Neutral
2. Fineness of silica fume: Over 80% of silica fume particles are smaller than 1 µm, with an average particle size ranging from 0.1 to 0.3 µm. The specific surface area is 20–28 m²/g. Its fineness and specific surface area are approximately 80–100 times that of cement and 50–70 times that of fly ash.
3. Particle morphology and mineral phase structure: During the formation process of silica fume, phase transformation under surface tension results in the formation of amorphous, spherical particles with a smooth surface. Some particles aggregate as clusters of multiple spheres. It is a highly active pozzolanic material with a very large specific surface area. In materials mixed with silica fume, the tiny spherical particles act as lubricants.

Specific Applications:
Microsilica can fill the pores between cement particles and, simultaneously, react with hydration products to form gel. It also reacts with alkaline materials like magnesium oxide to produce gel. When added in appropriate amounts to cement-based concrete, mortar, and refractory castables, silica fume can provide the following benefits: 1. Significantly improve compressive strength, flexural strength, impermeability, corrosion resistance, impact resistance, and wear resistance. 2. Retain water, prevent segregation and bleeding, and greatly reduce pumping resistance in concrete. 3. Significantly extend the service life of concrete. Especially in harsh environments such as chloride salt contamination, sulfate erosion, and high humidity, it can double or even multiply the durability of concrete. 4. Greatly reduce rebound in shotcrete and castables, and increase the thickness of single-layer spraying. 5. It is an essential component of high-strength concrete, with engineering applications already achieving C150 concrete. 6. It has about five times the efficiency of cement, reducing costs in ordinary concrete and low-cement castables while improving durability. 7. Effectively prevent alkali-aggregate reaction in concrete. 8. Improve the density of castable refractories. When coexisting with Al₂O₃, it更容易 promotes the formation of mullite phase, enhancing high-temperature strength and thermal shock resistance.

Scope of Application:
Commercial concrete, high-strength concrete, self-leveling concrete, unshaped refractories, dry-mix (premixed) mortar, high-strength non-shrink grout, wear-resistant industrial flooring, repair mortar, polymer mortar, thermal insulation mortar, impermeable concrete, concrete densifier, concrete anticorrosive agent, cement-based polymer waterproofing agent; reinforcement for rubber, plastics, unsaturated polyester, paints, coatings, and other polymer materials; modification of ceramic products, etc.

Application Fields:
1. Used in mortar and concrete: High-rise buildings, seaports and docks, reservoir dams, water conservancy, culverts and sluices, railways, highways, bridges, subways, tunnels, airport runways, concrete pavements, and anchor spraying reinforcement in coal mine tunnels, etc.
2. In the materials industry:
(1) High-performance, low-cement refractory castables and precast components, with a service life three times that of ordinary castables, refractory temperature increased by about 100°C, and significantly improved high-temperature strength and thermal shock resistance. Widely used in: coke ovens, ironmaking, steelmaking, rolling, non-ferrous metals, glass, ceramics, and power generation industries.
(2) Large tundish and ladle materials, permeable bricks, patching and repair materials, etc.
(3) Self-flowing refractory castables and applications in dry and wet shotcrete construction.
(4) Oxide-bonded silicon carbide products (e.g., kiln furniture, radiant tubes for ceramic kilns).
(5) High-temperature calcium silicate lightweight insulation materials.
(6) Alumina-mullite push plates for electroceramic kilns.
(7) High-temperature wear-resistant materials and products.
(8) Alumina and ceramic products.
(9) Sialon-bonded products. Currently, besides widespread use in castable refractories, it is also extensively applied in fused and sintered refractories.
3. New wall materials and finishing materials: (1) Polymer mortar for wall insulation, thermal insulation mortar, and interface agents. (2) Cement-based polymer waterproofing materials. (3) Lightweight aggregate energy-saving thermal insulation concrete and products. (4) Processing of interior and exterior wall putty powder for construction.