Is microsilica the same as silica fume?

Silica fume, also known as microsilica, is a fine-grain, thin, and very high surface area silica. The particle size of silica fume is around 1/100th the size of an average cement particle. The most commonly used unit is mesh. The main application is concrete and some undensified is used for refractory castable.

What is microsilica powder?

Silica fume, also known as micro silica is an amorphous (non-crystalline) polymorph of silicon dioxide, silica. It is an ultrafine powder collected as a by-product of the silicon and ferrosilicon alloy production and consists of spherical particles with an average particle diameter of 150 nm.

What is the specific gravity of microsilica?

The specific gravity of silica fume is generally in the range of 2.2 to 2.3 Around 500.000 MT of micro silica are sold to the construction industry world-wide and are used in fiber cement, concrete, oil-well drilling and even in polymers.

Is code for silica fume?

3.0 For the purpose of this standard, the definitions given in IS 4305 and the following shall apply. 3.1 Silica Fume — Very fine pozzolanic material, composed mostly of amorphous silica produced by electric arc furnaces as a byproduct of the production of elemental silicon or ferro-silicon alloys.

Why is microsilica used in concrete?

Microsilica or silica fume is an excellent admixture for concrete as it leads to better engineering properties. It reduces thermal cracking, improves durability, and increases strength. Silica fume concrete has a number of construction applications.

How do you use microsilica in concrete?

Micro-silica in concrete contributes to strength and durability two ways: As a pozzolanic material, micro-silica provides a more uniform distribution and a greater volume of hydration products. As a filler, micro-silica decreases the average size of pores in the cement paste.

What is microsilica made of?

Silica fume, also known as microsilica, is an amorphous polymorph of silicon dioxide, silica. It is a by-product of the carbothermic reduction of high purity quartz in electric arc furnaces in the production of silicon and ferrosilicon alloys.

How is microsilica made?

How does microsilica improve concrete?

Microsilica or silica fume is an excellent admixture for concrete as it leads to better engineering properties. It reduces thermal cracking, improves durability, and increases strength.

What is microsilica used for?

Is microsilica cementitious?

The extremely fine particles of microsilica (<1µm) act as a filler that can fit into space among cement particles. Because of its cementitious property, a partial replacement of cement with microsilica not only decreases the use of cement but also improves the mechanical properties of concrete.

What is the function of microsilica in concrete?

Microsilica in concrete improves its strength and durability as it provides more uniform distribution and a greater volume of hydration products, and decreases the average size of pores in the cement paste.

How does microsilica work in concrete?

HOW MICROSILICA WORKS IN CONCRETE. Microsilica in concrete contributes to strength and durability two ways: as a pozzolan, microsilica provides a more uniform distribution and a greater volume of hydration products; as a filler, microsilica decreases the average size of pores in the cement paste.

How do you attach microsilica to concrete?

There are two ways to add silica fume: (1) Input aggregate, then put silica fume and cement dry mix, then add water and other additives. (2) Put coarse aggregate + 75% water + silica fume + 50% fine aggregate, stir for 15-30 seconds, then add cement + admixture + 50% fine aggregate + 25% water, stir until uniform.