Silica Fume
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Silica Fume is a byproduct of the production of silicon and ferrosilicon alloys. It is a very fine powder, with particles about 100 times smaller than cement particles.
Silica Fume is added to concrete mixtures as a pozzolanic material, which means it reacts with calcium hydroxide in the presence of water to form additional cementitious compounds that increase the strength and durability of concrete. Silica Fume works by filling in the spaces between cement particles, which helps increase the concrete’s density and strength. It also reacts with calcium hydroxide in the cement to form a gel-like material, which helps to strengthen the concrete further.
Silica Fume can be supplied in two forms: Densified and Undensified.
Densified Silica Fume is a Silica Fume that has been treated and compressed into very fine pellets. Densified Silica Fumes have a higher bulk density than Undensified Silica Fumes. Densified Silica Fume is often used in high-strength concrete applications, such as bridges, high-rise buildings, and marine structures. It is also used in applications requiring a low water-to-cement ratio, such as precast concrete. Densified Silica Fume can improve concrete’s compressive strength, tensile strength, and durability.
Undensified Silica Fume, on the other hand, is a loose powder that has not been treated or compressed. It has a lower bulk density than Densified Silica Fume and is less uniform in size and shape. Undensified Silica Fume is often used in applications where a high surface area is desired, such as in shotcrete or as an admixture in self-compacting concrete. It is also used in precast concrete, improving the surface finish and reducing the risk of cracking.
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Silica Fume is a pozzolanic material that can improve sprayed concrete’s strength, durability, and impermeability.
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Silica Fume ((also known as Microsilica) plays a vital role as a filler material in the gypsum board manufacturing process, helping to improve the final product’s fire-retardant properties and overall performance. This is because Silica Fume is an excellent fire-retardant material due to its high content of Amorphous Silica and its small particle size, which allows it to penetrate deep into the material and fill any gaps or voids.
When added to the gypsum board manufacturing process, Silica Fume helps improve the board’s fire resistance by increasing its density and reducing the number of combustible materials present.
Silica fume is a pozzolanic material that can react with calcium hydroxide and other minerals in the gypsum core to produce additional calcium silicate hydrate (C-S-H) gel. This gel can help fill in the pores and voids in the core, improving the finished product’s strength and durability.
Adding silica fume to the gypsum core can improve its water resistance, which can help prevent damage from moisture exposure. The silica fume particles can fill in the pores and voids in the core, which can help to reduce the amount of water that can penetrate the core and cause it to degrade.
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Silica Fume is a fine-grain mineral additive used in plasterboard and drywall manufacture to improve the properties of the gypsum core. Using Silica Fume in plasterboard and drywall manufacture helps improve plasterboards’ strength, water resistance, and fire resistance, which can enhance their durability and safety.
The inclusion of Silica Fume serves several functions in plasterboard manufacture:
- Fire protection: Silica Fume can also improve the fire resistance of plasterboard and drywall products. When exposed to high temperatures, the silica fume particles can react with the gypsum to form a calcium silicate hydrate (C-S-H) gel that can help to protect the gypsum core from damage and prevent the spread of flames.
- Strength enhancement: Silica Fume is a pozzolanic material that can react with calcium hydroxide and other minerals in the gypsum core to produce additional calcium silicate hydrate (C-S-H) gel to improve the strength and durability of the finished product.
- Water resistance: can be improved, which helps prevent moisture exposure damage. Silica Fume particles can fill in the pores and voids in the core, which can help to reduce the amount of water that can penetrate the core and cause it to degrade.
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Silica Fume (also known as Microsilica) is a fine, powdery material added to the concrete mix to act as a functional filler additive crucial in manufacturing ready-mix concrete. It improves the pumping, workability, porosity control, durability, placement, and aesthetic finish of the finished concrete, making it a more reliable and versatile building material.
Here are some ways silica fume benefits the finished concrete:
- Pumping: Silica Fume improves the pumpability of concrete by reducing its viscosity. The smaller size of silica fume particles allows them to fill the gaps between the larger concrete particles, resulting in a more uniform and consistent mix. This results in concrete that can be easily pumped to the desired location.
- Workability: Silica Fume improves the workability of concrete by making it more cohesive and less prone to segregation. The addition of silica fume creates a dense packing of the particles, reducing the water-cement ratio and increasing the mix’s strength and workability. This makes it easier for the concrete to be placed, leveled, and finished.
- Porosity Control: Silica Fume fills the spaces between the cement particles, resulting in a denser, more compact concrete mix. This reduces the porosity of the concrete and makes it more resistant to water penetration, chemical attacks, and freeze-thaw cycles. The reduction in porosity also helps to control the shrinkage and cracking of the finished concrete.
- Durability: Silica Fume improves the durability of concrete by increasing its strength and resistance to environmental factors such as chemicals and moisture. Adding silica fume results in denser and stronger concrete, less prone to cracking and erosion over time.
- Placement and Aesthetic Finish: Silica Fume improves concrete’s placement and aesthetic finish by reducing segregation and increasing the homogeneity of the mix. The denser packing of the particles results in a more uniform texture and color, enhancing the finished concrete’s overall appearance.
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Silica Fume is a fine-grain mineral additive used in plasterboard and drywall manufacture to improve the properties of the gypsum core. The inclusion of Silica Fume serves to enhance fire protection in plasterboard and drywall products because when exposed to high temperatures, the silica fume particles can react with the gypsum to form a Calcium Silicate Hydrate (C-S-H) gel that can help to protect the gypsum core from damage and prevent the spread of flames.
The use of Silica Fume in plasterboard and drywall manufacture not only helps to improve the fire resistance of plasterboards but also the strength, water resistance, and which can enhance their durability and safety.
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Silica Fume is a highly effective additive in oilwell cementing applications because of its ability to improve the cement’s stability and pressure resistance strength. This is due to the addition of ultra-fine particles and organic admixtures that work together to create a high-strength cement that can withstand harsh conditions in oil wells.
Silica Fume is a pozzolanic material composed of excellent, amorphous spheres produced as a by-product in the manufacture of silicon metals. When Silica Fume is added to a cement slurry, it reacts with the calcium hydroxide produced during the hydration process to create an additional calcium silicate hydrate (C-S-H) gel. This gel is the main binder in cement, contributing significantly to the final product’s strength and durability.
One of the key advantages of using Silica Fume as an additive in oilwell cementing is that it can significantly increase the compressive strength of the cement. This is particularly important in manufacturing high-strength concrete, where the compressive strength after 28 days is greater than 80 MPa. The addition of Silica Fume can improve the compressive strength of the cement by up to 30%, making it an ideal additive for oilwell cementing applications where high-pressure resistance is required.