pretty much anything that make bubbles, it could be baking soda, vacuum chamber to suck the air and cause it to bubble, or salt as a spacer and put it in water to leach out the salt, giving u small air pockets in the aluminum.

@@voldschen232 i tried this method but nothing happened after adding foaming agent. sparks produced but aluminum remained melted and did not expand. is it necessary to cool it down as soon when foaming agent is added ?

@@marvelclips8601 I believe so, the issue with when it's still molten it's going to refill those spaces you created as soon as the bubbling stops.

@@voldschen232 this is exactly what my concept is. so i assume cooling is a major point here

I also tried this but it didn't work. Instead the foaming agents stayed on top and didn't mix with the aluminum melt

por favor avíseme su país?