Aluminum is a very active metal that reacts with water to displace hydrogen from water and form strong alumina. Since the surface of the aluminum powder particles exposed to the air has been oxidized by oxygen in the air, it forms an inert alumina protection，which hinders the contact of aluminum with water.
A certain amount of alkaline substances, such as calcium hydroxide, are present in the aerated concrete slurry, and the alumina can be dissolved in an alkaline solution to form a metaaluminate.
When the oxide film on the surface of the aluminum powder is dissolved, the metal aluminum reacts with water to displace hydrogen from the water and form a gelatinous aluminum hydroxide. However, it also interferes with the contact of water with the aluminum metal surface like alumina. So that the reaction cannot continue.
However, aluminum hydroxide can also be dissolved in an alkaline solution to form a metaaluminate. Thus, in an alkaline solution, aluminum can continuously react with water to form hydrogen gas until the aluminum metal is consumed. The hydrogen gas is uniformly distributed in the slurry in a substantially spherical shape, so that the volume of the slurry expands and hardens to form a porous structure of the silicate product.
Aluminum powder for AAC in our company is produced by dry grinding process. It has the advantages such as high active aluminum content, fast gas generating speed, easy dispersion, and long storage time.If you are looking for the products,please contact us .