About

Autoclaved Aerated Concrete is a Light weight product based on calcium silicate hydrates in which low density is attained by the inclusion of an expanding agent Aluminium powder resulting create porocity inside the block to make it light weight. Under controlled conditions Pond Ash, cement, Quick Lime Powder, Gypsum and water are mixed.Aluminium powder is used as a foaming agent in require quantity (depending on the prespecified density).When AAC is mixed and cast in forms several chemical reactions take place that gives AAC its light weight. Aluminium powder reacts with calcium hydroxide and water to form hydrogen. The hydrogen gas foams and doubles the volume of the raw mix.When side forms are removed from the material, it is solid but still soft. It is then cut into blocks then placed in an autoclave chamber for 12 hours. During this steam pressure for concrete formation, when the temperature reaches 180 to 190° Celsius by corresponding pressure reaches around12 bars,Silica available in Ash reacts with calcium hydroxide (with Cement and Quick Lime) to form calcium silicate hydrate (Stable Concrete). During the Autoclaving process, become shaped Tobermorite crystals (5Cao.6SI02.5H20) are formed as a major component of AAC.