Microsilica Fume By Xetex Industries Private Limited

CETEX MICROSILICA is a super pozzolan - a finely powdered material which when added to cementitious matter increases durability and gives higher strength. It complies with ASTM C1240.

ADVANTAGES
* Higher compressive strength by 10-20 %
* Reduces the rate of carbonation
* Lower permeability resistance to penetration of water, chloride & other chemicals
* Lower free lime formation - delays ettringite and thaumasite formation
* Controls bleeding in fresh concrete
* Lower Heat of Hydration, which prevents formation of cracks.

PROPERTIES:-
Appearance : Very fine powder
Colour : Grey
Odour : Odourless
Mean particle size : 25 microns
SiO2 A AcA A A A Silica : 85 % minimum
Humidity : 2 % maximum
Loss on ignition at 800A A A A C :4 % maximum


HOW IT WORKS

1. Pozzolonic effect : When water is added to cement, hydration occurs as shown below:

Ordinary Portland Cement (OPC) + H2O ---> CSH (Calcium silicate hydrate) + Ca(OH)2(Free lime)
The free lime does not contribute to strength of concrete. When combined with carbon dioxide, it forms a soluble salt, which leaches through the concrete causing efflorescence, a familiar architectural problem. Concrete is also more vulnerable to chemical attack and deterioration.
When CETEX Microsilica is added, the following reaction takes place:

Ca(OH)2 + SiO2 ---> H20 + CSH
The reaction reduces the amount of calcium hydroxide in the concrete.

2. Micro filler effect : It is an extremely fine material, with an average diameter much finer than the cement. It gets well distributed in the cementatious paste, thus blocking the bleed-water channels.